.mongorc.js

/**
 * @license
 * Lo-Dash 2.4.1 (Custom Build) <http://lodash.com/>
 * Build: `lodash -o ./dist/lodash.compat.js`
 * Copyright 2012-2013 The Dojo Foundation <http://dojofoundation.org/>
 * Based on Underscore.js 1.5.2 <http://underscorejs.org/LICENSE>
 * Copyright 2009-2013 Jeremy Ashkenas, DocumentCloud and Investigative Reporters & Editors
 * Available under MIT license <http://lodash.com/license>
 */
;(function() {

  /** Used as a safe reference for `undefined` in pre ES5 environments */
  var undefined;

  /** Used to pool arrays and objects used internally */
  var arrayPool = [],
      objectPool = [];

  /** Used to generate unique IDs */
  var idCounter = 0;

  /** Used internally to indicate various things */
  var indicatorObject = {};

  /** Used to prefix keys to avoid issues with `__proto__` and properties on `Object.prototype` */
  var keyPrefix = +new Date + '';

  /** Used as the size when optimizations are enabled for large arrays */
  var largeArraySize = 75;

  /** Used as the max size of the `arrayPool` and `objectPool` */
  var maxPoolSize = 40;

  /** Used to detect and test whitespace */
  var whitespace = (
    // whitespace
    ' \t\x0B\f\xA0\ufeff' +

    // line terminators
    '\n\r\u2028\u2029' +

    // unicode category "Zs" space separators
    '\u1680\u180e\u2000\u2001\u2002\u2003\u2004\u2005\u2006\u2007\u2008\u2009\u200a\u202f\u205f\u3000'
  );

  /** Used to match empty string literals in compiled template source */
  var reEmptyStringLeading = /\b__p \+= '';/g,
      reEmptyStringMiddle = /\b(__p \+=) '' \+/g,
      reEmptyStringTrailing = /(__e\(.*?\)|\b__t\)) \+\n'';/g;

  /**
   * Used to match ES6 template delimiters
   * http://people.mozilla.org/~jorendorff/es6-draft.html#sec-literals-string-literals
   */
  var reEsTemplate = /\$\{([^\\}]*(?:\\.[^\\}]*)*)\}/g;

  /** Used to match regexp flags from their coerced string values */
  var reFlags = /\w*$/;

  /** Used to detected named functions */
  var reFuncName = /^\s*function[ \n\r\t]+\w/;

  /** Used to match "interpolate" template delimiters */
  var reInterpolate = /<%=([\s\S]+?)%>/g;

  /** Used to match leading whitespace and zeros to be removed */
  var reLeadingSpacesAndZeros = RegExp('^[' + whitespace + ']*0+(?=.$)');

  /** Used to ensure capturing order of template delimiters */
  var reNoMatch = /($^)/;

  /** Used to detect functions containing a `this` reference */
  var reThis = /\bthis\b/;

  /** Used to match unescaped characters in compiled string literals */
  var reUnescapedString = /['\n\r\t\u2028\u2029\\]/g;

  /** Used to assign default `context` object properties */
  var contextProps = [
    'Array', 'Boolean', 'Date', 'Error', 'Function', 'Math', 'Number', 'Object',
    'RegExp', 'String', '_', 'attachEvent', 'clearTimeout', 'isFinite', 'isNaN',
    'parseInt', 'setTimeout'
  ];

  /** Used to fix the JScript [[DontEnum]] bug */
  var shadowedProps = [
    'constructor', 'hasOwnProperty', 'isPrototypeOf', 'propertyIsEnumerable',
    'toLocaleString', 'toString', 'valueOf'
  ];

  /** Used to make template sourceURLs easier to identify */
  var templateCounter = 0;

  /** `Object#toString` result shortcuts */
  var argsClass = '[object Arguments]',
      arrayClass = '[object Array]',
      boolClass = '[object Boolean]',
      dateClass = '[object Date]',
      errorClass = '[object Error]',
      funcClass = '[object Function]',
      numberClass = '[object Number]',
      objectClass = '[object Object]',
      regexpClass = '[object RegExp]',
      stringClass = '[object String]';

  /** Used to identify object classifications that `_.clone` supports */
  var cloneableClasses = {};
  cloneableClasses[funcClass] = false;
  cloneableClasses[argsClass] = cloneableClasses[arrayClass] =
  cloneableClasses[boolClass] = cloneableClasses[dateClass] =
  cloneableClasses[numberClass] = cloneableClasses[objectClass] =
  cloneableClasses[regexpClass] = cloneableClasses[stringClass] = true;

  /** Used as an internal `_.debounce` options object */
  var debounceOptions = {
    'leading': false,
    'maxWait': 0,
    'trailing': false
  };

  /** Used as the property descriptor for `__bindData__` */
  var descriptor = {
    'configurable': false,
    'enumerable': false,
    'value': null,
    'writable': false
  };

  /** Used as the data object for `iteratorTemplate` */
  var iteratorData = {
    'args': '',
    'array': null,
    'bottom': '',
    'firstArg': '',
    'init': '',
    'keys': null,
    'loop': '',
    'shadowedProps': null,
    'support': null,
    'top': '',
    'useHas': false
  };

  /** Used to determine if values are of the language type Object */
  var objectTypes = {
    'boolean': false,
    'function': true,
    'object': true,
    'number': false,
    'string': false,
    'undefined': false
  };

  /** Used to escape characters for inclusion in compiled string literals */
  var stringEscapes = {
    '\\': '\\',
    "'": "'",
    '\n': 'n',
    '\r': 'r',
    '\t': 't',
    '\u2028': 'u2028',
    '\u2029': 'u2029'
  };

  /** Used as a reference to the global object */
  var root = (objectTypes[typeof window] && window) || this;

  /** Detect free variable `exports` */
  var freeExports = objectTypes[typeof exports] && exports && !exports.nodeType && exports;

  /** Detect free variable `module` */
  var freeModule = objectTypes[typeof module] && module && !module.nodeType && module;

  /** Detect the popular CommonJS extension `module.exports` */
  var moduleExports = freeModule && freeModule.exports === freeExports && freeExports;

  /** Detect free variable `global` from Node.js or Browserified code and use it as `root` */
  var freeGlobal = objectTypes[typeof global] && global;
  if (freeGlobal && (freeGlobal.global === freeGlobal || freeGlobal.window === freeGlobal)) {
    root = freeGlobal;
  }

  /*--------------------------------------------------------------------------*/

  /**
   * The base implementation of `_.indexOf` without support for binary searches
   * or `fromIndex` constraints.
   *
   * @private
   * @param {Array} array The array to search.
   * @param {*} value The value to search for.
   * @param {number} [fromIndex=0] The index to search from.
   * @returns {number} Returns the index of the matched value or `-1`.
   */
  function baseIndexOf(array, value, fromIndex) {
    var index = (fromIndex || 0) - 1,
        length = array ? array.length : 0;

    while (++index < length) {
      if (array[index] === value) {
        return index;
      }
    }
    return -1;
  }

  /**
   * An implementation of `_.contains` for cache objects that mimics the return
   * signature of `_.indexOf` by returning `0` if the value is found, else `-1`.
   *
   * @private
   * @param {Object} cache The cache object to inspect.
   * @param {*} value The value to search for.
   * @returns {number} Returns `0` if `value` is found, else `-1`.
   */
  function cacheIndexOf(cache, value) {
    var type = typeof value;
    cache = cache.cache;

    if (type == 'boolean' || value == null) {
      return cache[value] ? 0 : -1;
    }
    if (type != 'number' && type != 'string') {
      type = 'object';
    }
    var key = type == 'number' ? value : keyPrefix + value;
    cache = (cache = cache[type]) && cache[key];

    return type == 'object'
      ? (cache && baseIndexOf(cache, value) > -1 ? 0 : -1)
      : (cache ? 0 : -1);
  }

  /**
   * Adds a given value to the corresponding cache object.
   *
   * @private
   * @param {*} value The value to add to the cache.
   */
  function cachePush(value) {
    var cache = this.cache,
        type = typeof value;

    if (type == 'boolean' || value == null) {
      cache[value] = true;
    } else {
      if (type != 'number' && type != 'string') {
        type = 'object';
      }
      var key = type == 'number' ? value : keyPrefix + value,
          typeCache = cache[type] || (cache[type] = {});

      if (type == 'object') {
        (typeCache[key] || (typeCache[key] = [])).push(value);
      } else {
        typeCache[key] = true;
      }
    }
  }

  /**
   * Used by `_.max` and `_.min` as the default callback when a given
   * collection is a string value.
   *
   * @private
   * @param {string} value The character to inspect.
   * @returns {number} Returns the code unit of given character.
   */
  function charAtCallback(value) {
    return value.charCodeAt(0);
  }

  /**
   * Used by `sortBy` to compare transformed `collection` elements, stable sorting
   * them in ascending order.
   *
   * @private
   * @param {Object} a The object to compare to `b`.
   * @param {Object} b The object to compare to `a`.
   * @returns {number} Returns the sort order indicator of `1` or `-1`.
   */
  function compareAscending(a, b) {
    var ac = a.criteria,
        bc = b.criteria,
        index = -1,
        length = ac.length;

    while (++index < length) {
      var value = ac[index],
          other = bc[index];

      if (value !== other) {
        if (value > other || typeof value == 'undefined') {
          return 1;
        }
        if (value < other || typeof other == 'undefined') {
          return -1;
        }
      }
    }
    // Fixes an `Array#sort` bug in the JS engine embedded in Adobe applications
    // that causes it, under certain circumstances, to return the same value for
    // `a` and `b`. See https://github.com/jashkenas/underscore/pull/1247
    //
    // This also ensures a stable sort in V8 and other engines.
    // See http://code.google.com/p/v8/issues/detail?id=90
    return a.index - b.index;
  }

  /**
   * Creates a cache object to optimize linear searches of large arrays.
   *
   * @private
   * @param {Array} [array=[]] The array to search.
   * @returns {null|Object} Returns the cache object or `null` if caching should not be used.
   */
  function createCache(array) {
    var index = -1,
        length = array.length,
        first = array[0],
        mid = array[(length / 2) | 0],
        last = array[length - 1];

    if (first && typeof first == 'object' &&
        mid && typeof mid == 'object' && last && typeof last == 'object') {
      return false;
    }
    var cache = getObject();
    cache['false'] = cache['null'] = cache['true'] = cache['undefined'] = false;

    var result = getObject();
    result.array = array;
    result.cache = cache;
    result.push = cachePush;

    while (++index < length) {
      result.push(array[index]);
    }
    return result;
  }

  /**
   * Used by `template` to escape characters for inclusion in compiled
   * string literals.
   *
   * @private
   * @param {string} match The matched character to escape.
   * @returns {string} Returns the escaped character.
   */
  function escapeStringChar(match) {
    return '\\' + stringEscapes[match];
  }

  /**
   * Gets an array from the array pool or creates a new one if the pool is empty.
   *
   * @private
   * @returns {Array} The array from the pool.
   */
  function getArray() {
    return arrayPool.pop() || [];
  }

  /**
   * Gets an object from the object pool or creates a new one if the pool is empty.
   *
   * @private
   * @returns {Object} The object from the pool.
   */
  function getObject() {
    return objectPool.pop() || {
      'array': null,
      'cache': null,
      'criteria': null,
      'false': false,
      'index': 0,
      'null': false,
      'number': null,
      'object': null,
      'push': null,
      'string': null,
      'true': false,
      'undefined': false,
      'value': null
    };
  }

  /**
   * Checks if `value` is a DOM node in IE < 9.
   *
   * @private
   * @param {*} value The value to check.
   * @returns {boolean} Returns `true` if the `value` is a DOM node, else `false`.
   */
  function isNode(value) {
    // IE < 9 presents DOM nodes as `Object` objects except they have `toString`
    // methods that are `typeof` "string" and still can coerce nodes to strings
    return typeof value.toString != 'function' && typeof (value + '') == 'string';
  }

  /**
   * Releases the given array back to the array pool.
   *
   * @private
   * @param {Array} [array] The array to release.
   */
  function releaseArray(array) {
    array.length = 0;
    if (arrayPool.length < maxPoolSize) {
      arrayPool.push(array);
    }
  }

  /**
   * Releases the given object back to the object pool.
   *
   * @private
   * @param {Object} [object] The object to release.
   */
  function releaseObject(object) {
    var cache = object.cache;
    if (cache) {
      releaseObject(cache);
    }
    object.array = object.cache = object.criteria = object.object = object.number = object.string = object.value = null;
    if (objectPool.length < maxPoolSize) {
      objectPool.push(object);
    }
  }

  /**
   * Slices the `collection` from the `start` index up to, but not including,
   * the `end` index.
   *
   * Note: This function is used instead of `Array#slice` to support node lists
   * in IE < 9 and to ensure dense arrays are returned.
   *
   * @private
   * @param {Array|Object|string} collection The collection to slice.
   * @param {number} start The start index.
   * @param {number} end The end index.
   * @returns {Array} Returns the new array.
   */
  function slice(array, start, end) {
    start || (start = 0);
    if (typeof end == 'undefined') {
      end = array ? array.length : 0;
    }
    var index = -1,
        length = end - start || 0,
        result = Array(length < 0 ? 0 : length);

    while (++index < length) {
      result[index] = array[start + index];
    }
    return result;
  }

  /*--------------------------------------------------------------------------*/

  /**
   * Create a new `lodash` function using the given context object.
   *
   * @static
   * @memberOf _
   * @category Utilities
   * @param {Object} [context=root] The context object.
   * @returns {Function} Returns the `lodash` function.
   */
  function runInContext(context) {
    // Avoid issues with some ES3 environments that attempt to use values, named
    // after built-in constructors like `Object`, for the creation of literals.
    // ES5 clears this up by stating that literals must use built-in constructors.
    // See http://es5.github.io/#x11.1.5.
    context = context ? _.defaults(root.Object(), context, _.pick(root, contextProps)) : root;

    /** Native constructor references */
    var Array = context.Array,
        Boolean = context.Boolean,
        Date = context.Date,
        Error = context.Error,
        Function = context.Function,
        Math = context.Math,
        Number = context.Number,
        Object = context.Object,
        RegExp = context.RegExp,
        String = context.String,
        TypeError = context.TypeError;

    /**
     * Used for `Array` method references.
     *
     * Normally `Array.prototype` would suffice, however, using an array literal
     * avoids issues in Narwhal.
     */
    var arrayRef = [];

    /** Used for native method references */
    var errorProto = Error.prototype,
        objectProto = Object.prototype,
        stringProto = String.prototype;

    /** Used to restore the original `_` reference in `noConflict` */
    var oldDash = context._;

    /** Used to resolve the internal [[Class]] of values */
    var toString = objectProto.toString;

    /** Used to detect if a method is native */
    var reNative = RegExp('^' +
      String(toString)
        .replace(/[.*+?^${}()|[\]\\]/g, '\\$&')
        .replace(/toString| for [^\]]+/g, '.*?') + '$'
    );

    /** Native method shortcuts */
    var ceil = Math.ceil,
        clearTimeout = context.clearTimeout,
        floor = Math.floor,
        fnToString = Function.prototype.toString,
        getPrototypeOf = isNative(getPrototypeOf = Object.getPrototypeOf) && getPrototypeOf,
        hasOwnProperty = objectProto.hasOwnProperty,
        push = arrayRef.push,
        propertyIsEnumerable = objectProto.propertyIsEnumerable,
        setTimeout = context.setTimeout,
        splice = arrayRef.splice,
        unshift = arrayRef.unshift;

    /** Used to set meta data on functions */
    var defineProperty = (function() {
      // IE 8 only accepts DOM elements
      try {
        var o = {},
            func = isNative(func = Object.defineProperty) && func,
            result = func(o, o, o) && func;
      } catch(e) { }
      return result;
    }());

    /* Native method shortcuts for methods with the same name as other `lodash` methods */
    var nativeCreate = isNative(nativeCreate = Object.create) && nativeCreate,
        nativeIsArray = isNative(nativeIsArray = Array.isArray) && nativeIsArray,
        nativeIsFinite = context.isFinite,
        nativeIsNaN = context.isNaN,
        nativeKeys = isNative(nativeKeys = Object.keys) && nativeKeys,
        nativeMax = Math.max,
        nativeMin = Math.min,
        nativeParseInt = context.parseInt,
        nativeRandom = Math.random;

    /** Used to lookup a built-in constructor by [[Class]] */
    var ctorByClass = {};
    ctorByClass[arrayClass] = Array;
    ctorByClass[boolClass] = Boolean;
    ctorByClass[dateClass] = Date;
    ctorByClass[funcClass] = Function;
    ctorByClass[objectClass] = Object;
    ctorByClass[numberClass] = Number;
    ctorByClass[regexpClass] = RegExp;
    ctorByClass[stringClass] = String;

    /** Used to avoid iterating non-enumerable properties in IE < 9 */
    var nonEnumProps = {};
    nonEnumProps[arrayClass] = nonEnumProps[dateClass] = nonEnumProps[numberClass] = { 'constructor': true, 'toLocaleString': true, 'toString': true, 'valueOf': true };
    nonEnumProps[boolClass] = nonEnumProps[stringClass] = { 'constructor': true, 'toString': true, 'valueOf': true };
    nonEnumProps[errorClass] = nonEnumProps[funcClass] = nonEnumProps[regexpClass] = { 'constructor': true, 'toString': true };
    nonEnumProps[objectClass] = { 'constructor': true };

    (function() {
      var length = shadowedProps.length;
      while (length--) {
        var key = shadowedProps[length];
        for (var className in nonEnumProps) {
          if (hasOwnProperty.call(nonEnumProps, className) && !hasOwnProperty.call(nonEnumProps[className], key)) {
            nonEnumProps[className][key] = false;
          }
        }
      }
    }());

    /*--------------------------------------------------------------------------*/

    /**
     * Creates a `lodash` object which wraps the given value to enable intuitive
     * method chaining.
     *
     * In addition to Lo-Dash methods, wrappers also have the following `Array` methods:
     * `concat`, `join`, `pop`, `push`, `reverse`, `shift`, `slice`, `sort`, `splice`,
     * and `unshift`
     *
     * Chaining is supported in custom builds as long as the `value` method is
     * implicitly or explicitly included in the build.
     *
     * The chainable wrapper functions are:
     * `after`, `assign`, `bind`, `bindAll`, `bindKey`, `chain`, `compact`,
     * `compose`, `concat`, `countBy`, `create`, `createCallback`, `curry`,
     * `debounce`, `defaults`, `defer`, `delay`, `difference`, `filter`, `flatten`,
     * `forEach`, `forEachRight`, `forIn`, `forInRight`, `forOwn`, `forOwnRight`,
     * `functions`, `groupBy`, `indexBy`, `initial`, `intersection`, `invert`,
     * `invoke`, `keys`, `map`, `max`, `memoize`, `merge`, `min`, `object`, `omit`,
     * `once`, `pairs`, `partial`, `partialRight`, `pick`, `pluck`, `pull`, `push`,
     * `range`, `reject`, `remove`, `rest`, `reverse`, `shuffle`, `slice`, `sort`,
     * `sortBy`, `splice`, `tap`, `throttle`, `times`, `toArray`, `transform`,
     * `union`, `uniq`, `unshift`, `unzip`, `values`, `where`, `without`, `wrap`,
     * and `zip`
     *
     * The non-chainable wrapper functions are:
     * `clone`, `cloneDeep`, `contains`, `escape`, `every`, `find`, `findIndex`,
     * `findKey`, `findLast`, `findLastIndex`, `findLastKey`, `has`, `identity`,
     * `indexOf`, `isArguments`, `isArray`, `isBoolean`, `isDate`, `isElement`,
     * `isEmpty`, `isEqual`, `isFinite`, `isFunction`, `isNaN`, `isNull`, `isNumber`,
     * `isObject`, `isPlainObject`, `isRegExp`, `isString`, `isUndefined`, `join`,
     * `lastIndexOf`, `mixin`, `noConflict`, `parseInt`, `pop`, `random`, `reduce`,
     * `reduceRight`, `result`, `shift`, `size`, `some`, `sortedIndex`, `runInContext`,
     * `template`, `unescape`, `uniqueId`, and `value`
     *
     * The wrapper functions `first` and `last` return wrapped values when `n` is
     * provided, otherwise they return unwrapped values.
     *
     * Explicit chaining can be enabled by using the `_.chain` method.
     *
     * @name _
     * @constructor
     * @category Chaining
     * @param {*} value The value to wrap in a `lodash` instance.
     * @returns {Object} Returns a `lodash` instance.
     * @example
     *
     * var wrapped = _([1, 2, 3]);
     *
     * // returns an unwrapped value
     * wrapped.reduce(function(sum, num) {
     *   return sum + num;
     * });
     * // => 6
     *
     * // returns a wrapped value
     * var squares = wrapped.map(function(num) {
     *   return num * num;
     * });
     *
     * _.isArray(squares);
     * // => false
     *
     * _.isArray(squares.value());
     * // => true
     */
    function lodash(value) {
      // don't wrap if already wrapped, even if wrapped by a different `lodash` constructor
      return (value && typeof value == 'object' && !isArray(value) && hasOwnProperty.call(value, '__wrapped__'))
       ? value
       : new lodashWrapper(value);
    }

    /**
     * A fast path for creating `lodash` wrapper objects.
     *
     * @private
     * @param {*} value The value to wrap in a `lodash` instance.
     * @param {boolean} chainAll A flag to enable chaining for all methods
     * @returns {Object} Returns a `lodash` instance.
     */
    function lodashWrapper(value, chainAll) {
      this.__chain__ = !!chainAll;
      this.__wrapped__ = value;
    }
    // ensure `new lodashWrapper` is an instance of `lodash`
    lodashWrapper.prototype = lodash.prototype;

    /**
     * An object used to flag environments features.
     *
     * @static
     * @memberOf _
     * @type Object
     */
    var support = lodash.support = {};

    (function() {
      var ctor = function() { this.x = 1; },
          object = { '0': 1, 'length': 1 },
          props = [];

      ctor.prototype = { 'valueOf': 1, 'y': 1 };
      for (var key in new ctor) { props.push(key); }
      for (key in arguments) { }

      /**
       * Detect if an `arguments` object's [[Class]] is resolvable (all but Firefox < 4, IE < 9).
       *
       * @memberOf _.support
       * @type boolean
       */
      support.argsClass = toString.call(arguments) == argsClass;

      /**
       * Detect if `arguments` objects are `Object` objects (all but Narwhal and Opera < 10.5).
       *
       * @memberOf _.support
       * @type boolean
       */
      support.argsObject = arguments.constructor == Object && !(arguments instanceof Array);

      /**
       * Detect if `name` or `message` properties of `Error.prototype` are
       * enumerable by default. (IE < 9, Safari < 5.1)
       *
       * @memberOf _.support
       * @type boolean
       */
      support.enumErrorProps = propertyIsEnumerable.call(errorProto, 'message') || propertyIsEnumerable.call(errorProto, 'name');

      /**
       * Detect if `prototype` properties are enumerable by default.
       *
       * Firefox < 3.6, Opera > 9.50 - Opera < 11.60, and Safari < 5.1
       * (if the prototype or a property on the prototype has been set)
       * incorrectly sets a function's `prototype` property [[Enumerable]]
       * value to `true`.
       *
       * @memberOf _.support
       * @type boolean
       */
      support.enumPrototypes = propertyIsEnumerable.call(ctor, 'prototype');

      /**
       * Detect if functions can be decompiled by `Function#toString`
       * (all but PS3 and older Opera mobile browsers & avoided in Windows 8 apps).
       *
       * @memberOf _.support
       * @type boolean
       */
      support.funcDecomp = !isNative(context.WinRTError) && reThis.test(runInContext);

      /**
       * Detect if `Function#name` is supported (all but IE).
       *
       * @memberOf _.support
       * @type boolean
       */
      support.funcNames = typeof Function.name == 'string';

      /**
       * Detect if `arguments` object indexes are non-enumerable
       * (Firefox < 4, IE < 9, PhantomJS, Safari < 5.1).
       *
       * @memberOf _.support
       * @type boolean
       */
      support.nonEnumArgs = key != 0;

      /**
       * Detect if properties shadowing those on `Object.prototype` are non-enumerable.
       *
       * In IE < 9 an objects own properties, shadowing non-enumerable ones, are
       * made non-enumerable as well (a.k.a the JScript [[DontEnum]] bug).
       *
       * @memberOf _.support
       * @type boolean
       */
      support.nonEnumShadows = !/valueOf/.test(props);

      /**
       * Detect if own properties are iterated after inherited properties (all but IE < 9).
       *
       * @memberOf _.support
       * @type boolean
       */
      support.ownLast = props[0] != 'x';

      /**
       * Detect if `Array#shift` and `Array#splice` augment array-like objects correctly.
       *
       * Firefox < 10, IE compatibility mode, and IE < 9 have buggy Array `shift()`
       * and `splice()` functions that fail to remove the last element, `value[0]`,
       * of array-like objects even though the `length` property is set to `0`.
       * The `shift()` method is buggy in IE 8 compatibility mode, while `splice()`
       * is buggy regardless of mode in IE < 9 and buggy in compatibility mode in IE 9.
       *
       * @memberOf _.support
       * @type boolean
       */
      support.spliceObjects = (arrayRef.splice.call(object, 0, 1), !object[0]);

      /**
       * Detect lack of support for accessing string characters by index.
       *
       * IE < 8 can't access characters by index and IE 8 can only access
       * characters by index on string literals.
       *
       * @memberOf _.support
       * @type boolean
       */
      support.unindexedChars = ('x'[0] + Object('x')[0]) != 'xx';

      /**
       * Detect if a DOM node's [[Class]] is resolvable (all but IE < 9)
       * and that the JS engine errors when attempting to coerce an object to
       * a string without a `toString` function.
       *
       * @memberOf _.support
       * @type boolean
       */
      try {
        support.nodeClass = !(toString.call(document) == objectClass && !({ 'toString': 0 } + ''));
      } catch(e) {
        support.nodeClass = true;
      }
    }(1));

    /**
     * By default, the template delimiters used by Lo-Dash are similar to those in
     * embedded Ruby (ERB). Change the following template settings to use alternative
     * delimiters.
     *
     * @static
     * @memberOf _
     * @type Object
     */
    lodash.templateSettings = {

      /**
       * Used to detect `data` property values to be HTML-escaped.
       *
       * @memberOf _.templateSettings
       * @type RegExp
       */
      'escape': /<%-([\s\S]+?)%>/g,

      /**
       * Used to detect code to be evaluated.
       *
       * @memberOf _.templateSettings
       * @type RegExp
       */
      'evaluate': /<%([\s\S]+?)%>/g,

      /**
       * Used to detect `data` property values to inject.
       *
       * @memberOf _.templateSettings
       * @type RegExp
       */
      'interpolate': reInterpolate,

      /**
       * Used to reference the data object in the template text.
       *
       * @memberOf _.templateSettings
       * @type string
       */
      'variable': '',

      /**
       * Used to import variables into the compiled template.
       *
       * @memberOf _.templateSettings
       * @type Object
       */
      'imports': {

        /**
         * A reference to the `lodash` function.
         *
         * @memberOf _.templateSettings.imports
         * @type Function
         */
        '_': lodash
      }
    };

    /*--------------------------------------------------------------------------*/

    /**
     * The template used to create iterator functions.
     *
     * @private
     * @param {Object} data The data object used to populate the text.
     * @returns {string} Returns the interpolated text.
     */
    var iteratorTemplate = function(obj) {

      var __p = 'var index, iterable = ' +
      (obj.firstArg) +
      ', result = ' +
      (obj.init) +
      ';\nif (!iterable) return result;\n' +
      (obj.top) +
      ';';
       if (obj.array) {
      __p += '\nvar length = iterable.length; index = -1;\nif (' +
      (obj.array) +
      ') {  ';
       if (support.unindexedChars) {
      __p += '\n  if (isString(iterable)) {\n    iterable = iterable.split(\'\')\n  }  ';
       }
      __p += '\n  while (++index < length) {\n    ' +
      (obj.loop) +
      ';\n  }\n}\nelse {  ';
       } else if (support.nonEnumArgs) {
      __p += '\n  var length = iterable.length; index = -1;\n  if (length && isArguments(iterable)) {\n    while (++index < length) {\n      index += \'\';\n      ' +
      (obj.loop) +
      ';\n    }\n  } else {  ';
       }

       if (support.enumPrototypes) {
      __p += '\n  var skipProto = typeof iterable == \'function\';\n  ';
       }

       if (support.enumErrorProps) {
      __p += '\n  var skipErrorProps = iterable === errorProto || iterable instanceof Error;\n  ';
       }

          var conditions = [];    if (support.enumPrototypes) { conditions.push('!(skipProto && index == "prototype")'); }    if (support.enumErrorProps)  { conditions.push('!(skipErrorProps && (index == "message" || index == "name"))'); }

       if (obj.useHas && obj.keys) {
      __p += '\n  var ownIndex = -1,\n      ownProps = objectTypes[typeof iterable] && keys(iterable),\n      length = ownProps ? ownProps.length : 0;\n\n  while (++ownIndex < length) {\n    index = ownProps[ownIndex];\n';
          if (conditions.length) {
      __p += '    if (' +
      (conditions.join(' && ')) +
      ') {\n  ';
       }
      __p +=
      (obj.loop) +
      ';    ';
       if (conditions.length) {
      __p += '\n    }';
       }
      __p += '\n  }  ';
       } else {
      __p += '\n  for (index in iterable) {\n';
          if (obj.useHas) { conditions.push("hasOwnProperty.call(iterable, index)"); }    if (conditions.length) {
      __p += '    if (' +
      (conditions.join(' && ')) +
      ') {\n  ';
       }
      __p +=
      (obj.loop) +
      ';    ';
       if (conditions.length) {
      __p += '\n    }';
       }
      __p += '\n  }    ';
       if (support.nonEnumShadows) {
      __p += '\n\n  if (iterable !== objectProto) {\n    var ctor = iterable.constructor,\n        isProto = iterable === (ctor && ctor.prototype),\n        className = iterable === stringProto ? stringClass : iterable === errorProto ? errorClass : toString.call(iterable),\n        nonEnum = nonEnumProps[className];\n      ';
       for (k = 0; k < 7; k++) {
      __p += '\n    index = \'' +
      (obj.shadowedProps[k]) +
      '\';\n    if ((!(isProto && nonEnum[index]) && hasOwnProperty.call(iterable, index))';
              if (!obj.useHas) {
      __p += ' || (!nonEnum[index] && iterable[index] !== objectProto[index])';
       }
      __p += ') {\n      ' +
      (obj.loop) +
      ';\n    }      ';
       }
      __p += '\n  }    ';
       }

       }

       if (obj.array || support.nonEnumArgs) {
      __p += '\n}';
       }
      __p +=
      (obj.bottom) +
      ';\nreturn result';

      return __p
    };

    /*--------------------------------------------------------------------------*/

    /**
     * The base implementation of `_.bind` that creates the bound function and
     * sets its meta data.
     *
     * @private
     * @param {Array} bindData The bind data array.
     * @returns {Function} Returns the new bound function.
     */
    function baseBind(bindData) {
      var func = bindData[0],
          partialArgs = bindData[2],
          thisArg = bindData[4];

      function bound() {
        // `Function#bind` spec
        // http://es5.github.io/#x15.3.4.5
        if (partialArgs) {
          // avoid `arguments` object deoptimizations by using `slice` instead
          // of `Array.prototype.slice.call` and not assigning `arguments` to a
          // variable as a ternary expression
          var args = slice(partialArgs);
          push.apply(args, arguments);
        }
        // mimic the constructor's `return` behavior
        // http://es5.github.io/#x13.2.2
        if (this instanceof bound) {
          // ensure `new bound` is an instance of `func`
          var thisBinding = baseCreate(func.prototype),
              result = func.apply(thisBinding, args || arguments);
          return isObject(result) ? result : thisBinding;
        }
        return func.apply(thisArg, args || arguments);
      }
      setBindData(bound, bindData);
      return bound;
    }

    /**
     * The base implementation of `_.clone` without argument juggling or support
     * for `thisArg` binding.
     *
     * @private
     * @param {*} value The value to clone.
     * @param {boolean} [isDeep=false] Specify a deep clone.
     * @param {Function} [callback] The function to customize cloning values.
     * @param {Array} [stackA=[]] Tracks traversed source objects.
     * @param {Array} [stackB=[]] Associates clones with source counterparts.
     * @returns {*} Returns the cloned value.
     */
    function baseClone(value, isDeep, callback, stackA, stackB) {
      if (callback) {
        var result = callback(value);
        if (typeof result != 'undefined') {
          return result;
        }
      }
      // inspect [[Class]]
      var isObj = isObject(value);
      if (isObj) {
        var className = toString.call(value);
        if (!cloneableClasses[className] || (!support.nodeClass && isNode(value))) {
          return value;
        }
        var ctor = ctorByClass[className];
        switch (className) {
          case boolClass:
          case dateClass:
            return new ctor(+value);

          case numberClass:
          case stringClass:
            return new ctor(value);

          case regexpClass:
            result = ctor(value.source, reFlags.exec(value));
            result.lastIndex = value.lastIndex;
            return result;
        }
      } else {
        return value;
      }
      var isArr = isArray(value);
      if (isDeep) {
        // check for circular references and return corresponding clone
        var initedStack = !stackA;
        stackA || (stackA = getArray());
        stackB || (stackB = getArray());

        var length = stackA.length;
        while (length--) {
          if (stackA[length] == value) {
            return stackB[length];
          }
        }
        result = isArr ? ctor(value.length) : {};
      }
      else {
        result = isArr ? slice(value) : assign({}, value);
      }
      // add array properties assigned by `RegExp#exec`
      if (isArr) {
        if (hasOwnProperty.call(value, 'index')) {
          result.index = value.index;
        }
        if (hasOwnProperty.call(value, 'input')) {
          result.input = value.input;
        }
      }
      // exit for shallow clone
      if (!isDeep) {
        return result;
      }
      // add the source value to the stack of traversed objects
      // and associate it with its clone
      stackA.push(value);
      stackB.push(result);

      // recursively populate clone (susceptible to call stack limits)
      (isArr ? baseEach : forOwn)(value, function(objValue, key) {
        result[key] = baseClone(objValue, isDeep, callback, stackA, stackB);
      });

      if (initedStack) {
        releaseArray(stackA);
        releaseArray(stackB);
      }
      return result;
    }

    /**
     * The base implementation of `_.create` without support for assigning
     * properties to the created object.
     *
     * @private
     * @param {Object} prototype The object to inherit from.
     * @returns {Object} Returns the new object.
     */
    function baseCreate(prototype, properties) {
      return isObject(prototype) ? nativeCreate(prototype) : {};
    }
    // fallback for browsers without `Object.create`
    if (!nativeCreate) {
      baseCreate = (function() {
        function Object() {}
        return function(prototype) {
          if (isObject(prototype)) {
            Object.prototype = prototype;
            var result = new Object;
            Object.prototype = null;
          }
          return result || context.Object();
        };
      }());
    }

    /**
     * The base implementation of `_.createCallback` without support for creating
     * "_.pluck" or "_.where" style callbacks.
     *
     * @private
     * @param {*} [func=identity] The value to convert to a callback.
     * @param {*} [thisArg] The `this` binding of the created callback.
     * @param {number} [argCount] The number of arguments the callback accepts.
     * @returns {Function} Returns a callback function.
     */
    function baseCreateCallback(func, thisArg, argCount) {
      if (typeof func != 'function') {
        return identity;
      }
      // exit early for no `thisArg` or already bound by `Function#bind`
      if (typeof thisArg == 'undefined' || !('prototype' in func)) {
        return func;
      }
      var bindData = func.__bindData__;
      if (typeof bindData == 'undefined') {
        if (support.funcNames) {
          bindData = !func.name;
        }
        bindData = bindData || !support.funcDecomp;
        if (!bindData) {
          var source = fnToString.call(func);
          if (!support.funcNames) {
            bindData = !reFuncName.test(source);
          }
          if (!bindData) {
            // checks if `func` references the `this` keyword and stores the result
            bindData = reThis.test(source);
            setBindData(func, bindData);
          }
        }
      }
      // exit early if there are no `this` references or `func` is bound
      if (bindData === false || (bindData !== true && bindData[1] & 1)) {
        return func;
      }
      switch (argCount) {
        case 1: return function(value) {
          return func.call(thisArg, value);
        };
        case 2: return function(a, b) {
          return func.call(thisArg, a, b);
        };
        case 3: return function(value, index, collection) {
          return func.call(thisArg, value, index, collection);
        };
        case 4: return function(accumulator, value, index, collection) {
          return func.call(thisArg, accumulator, value, index, collection);
        };
      }
      return bind(func, thisArg);
    }

    /**
     * The base implementation of `createWrapper` that creates the wrapper and
     * sets its meta data.
     *
     * @private
     * @param {Array} bindData The bind data array.
     * @returns {Function} Returns the new function.
     */
    function baseCreateWrapper(bindData) {
      var func = bindData[0],
          bitmask = bindData[1],
          partialArgs = bindData[2],
          partialRightArgs = bindData[3],
          thisArg = bindData[4],
          arity = bindData[5];

      var isBind = bitmask & 1,
          isBindKey = bitmask & 2,
          isCurry = bitmask & 4,
          isCurryBound = bitmask & 8,
          key = func;

      function bound() {
        var thisBinding = isBind ? thisArg : this;
        if (partialArgs) {
          var args = slice(partialArgs);
          push.apply(args, arguments);
        }
        if (partialRightArgs || isCurry) {
          args || (args = slice(arguments));
          if (partialRightArgs) {
            push.apply(args, partialRightArgs);
          }
          if (isCurry && args.length < arity) {
            bitmask |= 16 & ~32;
            return baseCreateWrapper([func, (isCurryBound ? bitmask : bitmask & ~3), args, null, thisArg, arity]);
          }
        }
        args || (args = arguments);
        if (isBindKey) {
          func = thisBinding[key];
        }
        if (this instanceof bound) {
          thisBinding = baseCreate(func.prototype);
          var result = func.apply(thisBinding, args);
          return isObject(result) ? result : thisBinding;
        }
        return func.apply(thisBinding, args);
      }
      setBindData(bound, bindData);
      return bound;
    }

    /**
     * The base implementation of `_.difference` that accepts a single array
     * of values to exclude.
     *
     * @private
     * @param {Array} array The array to process.
     * @param {Array} [values] The array of values to exclude.
     * @returns {Array} Returns a new array of filtered values.
     */
    function baseDifference(array, values) {
      var index = -1,
          indexOf = getIndexOf(),
          length = array ? array.length : 0,
          isLarge = length >= largeArraySize && indexOf === baseIndexOf,
          result = [];

      if (isLarge) {
        var cache = createCache(values);
        if (cache) {
          indexOf = cacheIndexOf;
          values = cache;
        } else {
          isLarge = false;
        }
      }
      while (++index < length) {
        var value = array[index];
        if (indexOf(values, value) < 0) {
          result.push(value);
        }
      }
      if (isLarge) {
        releaseObject(values);
      }
      return result;
    }

    /**
     * The base implementation of `_.flatten` without support for callback
     * shorthands or `thisArg` binding.
     *
     * @private
     * @param {Array} array The array to flatten.
     * @param {boolean} [isShallow=false] A flag to restrict flattening to a single level.
     * @param {boolean} [isStrict=false] A flag to restrict flattening to arrays and `arguments` objects.
     * @param {number} [fromIndex=0] The index to start from.
     * @returns {Array} Returns a new flattened array.
     */
    function baseFlatten(array, isShallow, isStrict, fromIndex) {
      var index = (fromIndex || 0) - 1,
          length = array ? array.length : 0,
          result = [];

      while (++index < length) {
        var value = array[index];

        if (value && typeof value == 'object' && typeof value.length == 'number'
            && (isArray(value) || isArguments(value))) {
          // recursively flatten arrays (susceptible to call stack limits)
          if (!isShallow) {
            value = baseFlatten(value, isShallow, isStrict);
          }
          var valIndex = -1,
              valLength = value.length,
              resIndex = result.length;

          result.length += valLength;
          while (++valIndex < valLength) {
            result[resIndex++] = value[valIndex];
          }
        } else if (!isStrict) {
          result.push(value);
        }
      }
      return result;
    }

    /**
     * The base implementation of `_.isEqual`, without support for `thisArg` binding,
     * that allows partial "_.where" style comparisons.
     *
     * @private
     * @param {*} a The value to compare.
     * @param {*} b The other value to compare.
     * @param {Function} [callback] The function to customize comparing values.
     * @param {Function} [isWhere=false] A flag to indicate performing partial comparisons.
     * @param {Array} [stackA=[]] Tracks traversed `a` objects.
     * @param {Array} [stackB=[]] Tracks traversed `b` objects.
     * @returns {boolean} Returns `true` if the values are equivalent, else `false`.
     */
    function baseIsEqual(a, b, callback, isWhere, stackA, stackB) {
      // used to indicate that when comparing objects, `a` has at least the properties of `b`
      if (callback) {
        var result = callback(a, b);
        if (typeof result != 'undefined') {
          return !!result;
        }
      }
      // exit early for identical values
      if (a === b) {
        // treat `+0` vs. `-0` as not equal
        return a !== 0 || (1 / a == 1 / b);
      }
      var type = typeof a,
          otherType = typeof b;

      // exit early for unlike primitive values
      if (a === a &&
          !(a && objectTypes[type]) &&
          !(b && objectTypes[otherType])) {
        return false;
      }
      // exit early for `null` and `undefined` avoiding ES3's Function#call behavior
      // http://es5.github.io/#x15.3.4.4
      if (a == null || b == null) {
        return a === b;
      }
      // compare [[Class]] names
      var className = toString.call(a),
          otherClass = toString.call(b);

      if (className == argsClass) {
        className = objectClass;
      }
      if (otherClass == argsClass) {
        otherClass = objectClass;
      }
      if (className != otherClass) {
        return false;
      }
      switch (className) {
        case boolClass:
        case dateClass:
          // coerce dates and booleans to numbers, dates to milliseconds and booleans
          // to `1` or `0` treating invalid dates coerced to `NaN` as not equal
          return +a == +b;

        case numberClass:
          // treat `NaN` vs. `NaN` as equal
          return (a != +a)
            ? b != +b
            // but treat `+0` vs. `-0` as not equal
            : (a == 0 ? (1 / a == 1 / b) : a == +b);

        case regexpClass:
        case stringClass:
          // coerce regexes to strings (http://es5.github.io/#x15.10.6.4)
          // treat string primitives and their corresponding object instances as equal
          return a == String(b);
      }
      var isArr = className == arrayClass;
      if (!isArr) {
        // unwrap any `lodash` wrapped values
        var aWrapped = hasOwnProperty.call(a, '__wrapped__'),
            bWrapped = hasOwnProperty.call(b, '__wrapped__');

        if (aWrapped || bWrapped) {
          return baseIsEqual(aWrapped ? a.__wrapped__ : a, bWrapped ? b.__wrapped__ : b, callback, isWhere, stackA, stackB);
        }
        // exit for functions and DOM nodes
        if (className != objectClass || (!support.nodeClass && (isNode(a) || isNode(b)))) {
          return false;
        }
        // in older versions of Opera, `arguments` objects have `Array` constructors
        var ctorA = !support.argsObject && isArguments(a) ? Object : a.constructor,
            ctorB = !support.argsObject && isArguments(b) ? Object : b.constructor;

        // non `Object` object instances with different constructors are not equal
        if (ctorA != ctorB &&
              !(isFunction(ctorA) && ctorA instanceof ctorA && isFunction(ctorB) && ctorB instanceof ctorB) &&
              ('constructor' in a && 'constructor' in b)
            ) {
          return false;
        }
      }
      // assume cyclic structures are equal
      // the algorithm for detecting cyclic structures is adapted from ES 5.1
      // section 15.12.3, abstract operation `JO` (http://es5.github.io/#x15.12.3)
      var initedStack = !stackA;
      stackA || (stackA = getArray());
      stackB || (stackB = getArray());

      var length = stackA.length;
      while (length--) {
        if (stackA[length] == a) {
          return stackB[length] == b;
        }
      }
      var size = 0;
      result = true;

      // add `a` and `b` to the stack of traversed objects
      stackA.push(a);
      stackB.push(b);

      // recursively compare objects and arrays (susceptible to call stack limits)
      if (isArr) {
        // compare lengths to determine if a deep comparison is necessary
        length = a.length;
        size = b.length;
        result = size == length;

        if (result || isWhere) {
          // deep compare the contents, ignoring non-numeric properties
          while (size--) {
            var index = length,
                value = b[size];

            if (isWhere) {
              while (index--) {
                if ((result = baseIsEqual(a[index], value, callback, isWhere, stackA, stackB))) {
                  break;
                }
              }
            } else if (!(result = baseIsEqual(a[size], value, callback, isWhere, stackA, stackB))) {
              break;
            }
          }
        }
      }
      else {
        // deep compare objects using `forIn`, instead of `forOwn`, to avoid `Object.keys`
        // which, in this case, is more costly
        forIn(b, function(value, key, b) {
          if (hasOwnProperty.call(b, key)) {
            // count the number of properties.
            size++;
            // deep compare each property value.
            return (result = hasOwnProperty.call(a, key) && baseIsEqual(a[key], value, callback, isWhere, stackA, stackB));
          }
        });

        if (result && !isWhere) {
          // ensure both objects have the same number of properties
          forIn(a, function(value, key, a) {
            if (hasOwnProperty.call(a, key)) {
              // `size` will be `-1` if `a` has more properties than `b`
              return (result = --size > -1);
            }
          });
        }
      }
      stackA.pop();
      stackB.pop();

      if (initedStack) {
        releaseArray(stackA);
        releaseArray(stackB);
      }
      return result;
    }

    /**
     * The base implementation of `_.merge` without argument juggling or support
     * for `thisArg` binding.
     *
     * @private
     * @param {Object} object The destination object.
     * @param {Object} source The source object.
     * @param {Function} [callback] The function to customize merging properties.
     * @param {Array} [stackA=[]] Tracks traversed source objects.
     * @param {Array} [stackB=[]] Associates values with source counterparts.
     */
    function baseMerge(object, source, callback, stackA, stackB) {
      (isArray(source) ? forEach : forOwn)(source, function(source, key) {
        var found,
            isArr,
            result = source,
            value = object[key];

        if (source && ((isArr = isArray(source)) || isPlainObject(source))) {
          // avoid merging previously merged cyclic sources
          var stackLength = stackA.length;
          while (stackLength--) {
            if ((found = stackA[stackLength] == source)) {
              value = stackB[stackLength];
              break;
            }
          }
          if (!found) {
            var isShallow;
            if (callback) {
              result = callback(value, source);
              if ((isShallow = typeof result != 'undefined')) {
                value = result;
              }
            }
            if (!isShallow) {
              value = isArr
                ? (isArray(value) ? value : [])
                : (isPlainObject(value) ? value : {});
            }
            // add `source` and associated `value` to the stack of traversed objects
            stackA.push(source);
            stackB.push(value);

            // recursively merge objects and arrays (susceptible to call stack limits)
            if (!isShallow) {
              baseMerge(value, source, callback, stackA, stackB);
            }
          }
        }
        else {
          if (callback) {
            result = callback(value, source);
            if (typeof result == 'undefined') {
              result = source;
            }
          }
          if (typeof result != 'undefined') {
            value = result;
          }
        }
        object[key] = value;
      });
    }

    /**
     * The base implementation of `_.random` without argument juggling or support
     * for returning floating-point numbers.
     *
     * @private
     * @param {number} min The minimum possible value.
     * @param {number} max The maximum possible value.
     * @returns {number} Returns a random number.
     */
    function baseRandom(min, max) {
      return min + floor(nativeRandom() * (max - min + 1));
    }

    /**
     * The base implementation of `_.uniq` without support for callback shorthands
     * or `thisArg` binding.
     *
     * @private
     * @param {Array} array The array to process.
     * @param {boolean} [isSorted=false] A flag to indicate that `array` is sorted.
     * @param {Function} [callback] The function called per iteration.
     * @returns {Array} Returns a duplicate-value-free array.
     */
    function baseUniq(array, isSorted, callback) {
      var index = -1,
          indexOf = getIndexOf(),
          length = array ? array.length : 0,
          result = [];

      var isLarge = !isSorted && length >= largeArraySize && indexOf === baseIndexOf,
          seen = (callback || isLarge) ? getArray() : result;

      if (isLarge) {
        var cache = createCache(seen);
        indexOf = cacheIndexOf;
        seen = cache;
      }
      while (++index < length) {
        var value = array[index],
            computed = callback ? callback(value, index, array) : value;

        if (isSorted
              ? !index || seen[seen.length - 1] !== computed
              : indexOf(seen, computed) < 0
            ) {
          if (callback || isLarge) {
            seen.push(computed);
          }
          result.push(value);
        }
      }
      if (isLarge) {
        releaseArray(seen.array);
        releaseObject(seen);
      } else if (callback) {
        releaseArray(seen);
      }
      return result;
    }

    /**
     * Creates a function that aggregates a collection, creating an object composed
     * of keys generated from the results of running each element of the collection
     * through a callback. The given `setter` function sets the keys and values
     * of the composed object.
     *
     * @private
     * @param {Function} setter The setter function.
     * @returns {Function} Returns the new aggregator function.
     */
    function createAggregator(setter) {
      return function(collection, callback, thisArg) {
        var result = {};
        callback = lodash.createCallback(callback, thisArg, 3);

        if (isArray(collection)) {
          var index = -1,
              length = collection.length;

          while (++index < length) {
            var value = collection[index];
            setter(result, value, callback(value, index, collection), collection);
          }
        } else {
          baseEach(collection, function(value, key, collection) {
            setter(result, value, callback(value, key, collection), collection);
          });
        }
        return result;
      };
    }

    /**
     * Creates a function that, when called, either curries or invokes `func`
     * with an optional `this` binding and partially applied arguments.
     *
     * @private
     * @param {Function|string} func The function or method name to reference.
     * @param {number} bitmask The bitmask of method flags to compose.
     *  The bitmask may be composed of the following flags:
     *  1 - `_.bind`
     *  2 - `_.bindKey`
     *  4 - `_.curry`
     *  8 - `_.curry` (bound)
     *  16 - `_.partial`
     *  32 - `_.partialRight`
     * @param {Array} [partialArgs] An array of arguments to prepend to those
     *  provided to the new function.
     * @param {Array} [partialRightArgs] An array of arguments to append to those
     *  provided to the new function.
     * @param {*} [thisArg] The `this` binding of `func`.
     * @param {number} [arity] The arity of `func`.
     * @returns {Function} Returns the new function.
     */
    function createWrapper(func, bitmask, partialArgs, partialRightArgs, thisArg, arity) {
      var isBind = bitmask & 1,
          isBindKey = bitmask & 2,
          isCurry = bitmask & 4,
          isCurryBound = bitmask & 8,
          isPartial = bitmask & 16,
          isPartialRight = bitmask & 32;

      if (!isBindKey && !isFunction(func)) {
        throw new TypeError;
      }
      if (isPartial && !partialArgs.length) {
        bitmask &= ~16;
        isPartial = partialArgs = false;
      }
      if (isPartialRight && !partialRightArgs.length) {
        bitmask &= ~32;
        isPartialRight = partialRightArgs = false;
      }
      var bindData = func && func.__bindData__;
      if (bindData && bindData !== true) {
        // clone `bindData`
        bindData = slice(bindData);
        if (bindData[2]) {
          bindData[2] = slice(bindData[2]);
        }
        if (bindData[3]) {
          bindData[3] = slice(bindData[3]);
        }
        // set `thisBinding` is not previously bound
        if (isBind && !(bindData[1] & 1)) {
          bindData[4] = thisArg;
        }
        // set if previously bound but not currently (subsequent curried functions)
        if (!isBind && bindData[1] & 1) {
          bitmask |= 8;
        }
        // set curried arity if not yet set
        if (isCurry && !(bindData[1] & 4)) {
          bindData[5] = arity;
        }
        // append partial left arguments
        if (isPartial) {
          push.apply(bindData[2] || (bindData[2] = []), partialArgs);
        }
        // append partial right arguments
        if (isPartialRight) {
          unshift.apply(bindData[3] || (bindData[3] = []), partialRightArgs);
        }
        // merge flags
        bindData[1] |= bitmask;
        return createWrapper.apply(null, bindData);
      }
      // fast path for `_.bind`
      var creater = (bitmask == 1 || bitmask === 17) ? baseBind : baseCreateWrapper;
      return creater([func, bitmask, partialArgs, partialRightArgs, thisArg, arity]);
    }

    /**
     * Creates compiled iteration functions.
     *
     * @private
     * @param {...Object} [options] The compile options object(s).
     * @param {string} [options.array] Code to determine if the iterable is an array or array-like.
     * @param {boolean} [options.useHas] Specify using `hasOwnProperty` checks in the object loop.
     * @param {Function} [options.keys] A reference to `_.keys` for use in own property iteration.
     * @param {string} [options.args] A comma separated string of iteration function arguments.
     * @param {string} [options.top] Code to execute before the iteration branches.
     * @param {string} [options.loop] Code to execute in the object loop.
     * @param {string} [options.bottom] Code to execute after the iteration branches.
     * @returns {Function} Returns the compiled function.
     */
    function createIterator() {
      // data properties
      iteratorData.shadowedProps = shadowedProps;

      // iterator options
      iteratorData.array = iteratorData.bottom = iteratorData.loop = iteratorData.top = '';
      iteratorData.init = 'iterable';
      iteratorData.useHas = true;

      // merge options into a template data object
      for (var object, index = 0; object = arguments[index]; index++) {
        for (var key in object) {
          iteratorData[key] = object[key];
        }
      }
      var args = iteratorData.args;
      iteratorData.firstArg = /^[^,]+/.exec(args)[0];

      // create the function factory
      var factory = Function(
          'baseCreateCallback, errorClass, errorProto, hasOwnProperty, ' +
          'indicatorObject, isArguments, isArray, isString, keys, objectProto, ' +
          'objectTypes, nonEnumProps, stringClass, stringProto, toString',
        'return function(' + args + ') {\n' + iteratorTemplate(iteratorData) + '\n}'
      );

      // return the compiled function
      return factory(
        baseCreateCallback, errorClass, errorProto, hasOwnProperty,
        indicatorObject, isArguments, isArray, isString, iteratorData.keys, objectProto,
        objectTypes, nonEnumProps, stringClass, stringProto, toString
      );
    }

    /**
     * Used by `escape` to convert characters to HTML entities.
     *
     * @private
     * @param {string} match The matched character to escape.
     * @returns {string} Returns the escaped character.
     */
    function escapeHtmlChar(match) {
      return htmlEscapes[match];
    }

    /**
     * Gets the appropriate "indexOf" function. If the `_.indexOf` method is
     * customized, this method returns the custom method, otherwise it returns
     * the `baseIndexOf` function.
     *
     * @private
     * @returns {Function} Returns the "indexOf" function.
     */
    function getIndexOf() {
      var result = (result = lodash.indexOf) === indexOf ? baseIndexOf : result;
      return result;
    }

    /**
     * Checks if `value` is a native function.
     *
     * @private
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if the `value` is a native function, else `false`.
     */
    function isNative(value) {
      return typeof value == 'function' && reNative.test(value);
    }

    /**
     * Sets `this` binding data on a given function.
     *
     * @private
     * @param {Function} func The function to set data on.
     * @param {Array} value The data array to set.
     */
    var setBindData = !defineProperty ? noop : function(func, value) {
      descriptor.value = value;
      defineProperty(func, '__bindData__', descriptor);
    };

    /**
     * A fallback implementation of `isPlainObject` which checks if a given value
     * is an object created by the `Object` constructor, assuming objects created
     * by the `Object` constructor have no inherited enumerable properties and that
     * there are no `Object.prototype` extensions.
     *
     * @private
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if `value` is a plain object, else `false`.
     */
    function shimIsPlainObject(value) {
      var ctor,
          result;

      // avoid non Object objects, `arguments` objects, and DOM elements
      if (!(value && toString.call(value) == objectClass) ||
          (ctor = value.constructor, isFunction(ctor) && !(ctor instanceof ctor)) ||
          (!support.argsClass && isArguments(value)) ||
          (!support.nodeClass && isNode(value))) {
        return false;
      }
      // IE < 9 iterates inherited properties before own properties. If the first
      // iterated property is an object's own property then there are no inherited
      // enumerable properties.
      if (support.ownLast) {
        forIn(value, function(value, key, object) {
          result = hasOwnProperty.call(object, key);
          return false;
        });
        return result !== false;
      }
      // In most environments an object's own properties are iterated before
      // its inherited properties. If the last iterated property is an object's
      // own property then there are no inherited enumerable properties.
      forIn(value, function(value, key) {
        result = key;
      });
      return typeof result == 'undefined' || hasOwnProperty.call(value, result);
    }

    /**
     * Used by `unescape` to convert HTML entities to characters.
     *
     * @private
     * @param {string} match The matched character to unescape.
     * @returns {string} Returns the unescaped character.
     */
    function unescapeHtmlChar(match) {
      return htmlUnescapes[match];
    }

    /*--------------------------------------------------------------------------*/

    /**
     * Checks if `value` is an `arguments` object.
     *
     * @static
     * @memberOf _
     * @category Objects
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if the `value` is an `arguments` object, else `false`.
     * @example
     *
     * (function() { return _.isArguments(arguments); })(1, 2, 3);
     * // => true
     *
     * _.isArguments([1, 2, 3]);
     * // => false
     */
    function isArguments(value) {
      return value && typeof value == 'object' && typeof value.length == 'number' &&
        toString.call(value) == argsClass || false;
    }
    // fallback for browsers that can't detect `arguments` objects by [[Class]]
    if (!support.argsClass) {
      isArguments = function(value) {
        return value && typeof value == 'object' && typeof value.length == 'number' &&
          hasOwnProperty.call(value, 'callee') && !propertyIsEnumerable.call(value, 'callee') || false;
      };
    }

    /**
     * Checks if `value` is an array.
     *
     * @static
     * @memberOf _
     * @type Function
     * @category Objects
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if the `value` is an array, else `false`.
     * @example
     *
     * (function() { return _.isArray(arguments); })();
     * // => false
     *
     * _.isArray([1, 2, 3]);
     * // => true
     */
    var isArray = nativeIsArray || function(value) {
      return value && typeof value == 'object' && typeof value.length == 'number' &&
        toString.call(value) == arrayClass || false;
    };

    /**
     * A fallback implementation of `Object.keys` which produces an array of the
     * given object's own enumerable property names.
     *
     * @private
     * @type Function
     * @param {Object} object The object to inspect.
     * @returns {Array} Returns an array of property names.
     */
    var shimKeys = createIterator({
      'args': 'object',
      'init': '[]',
      'top': 'if (!(objectTypes[typeof object])) return result',
      'loop': 'result.push(index)'
    });

    /**
     * Creates an array composed of the own enumerable property names of an object.
     *
     * @static
     * @memberOf _
     * @category Objects
     * @param {Object} object The object to inspect.
     * @returns {Array} Returns an array of property names.
     * @example
     *
     * _.keys({ 'one': 1, 'two': 2, 'three': 3 });
     * // => ['one', 'two', 'three'] (property order is not guaranteed across environments)
     */
    var keys = !nativeKeys ? shimKeys : function(object) {
      if (!isObject(object)) {
        return [];
      }
      if ((support.enumPrototypes && typeof object == 'function') ||
          (support.nonEnumArgs && object.length && isArguments(object))) {
        return shimKeys(object);
      }
      return nativeKeys(object);
    };

    /** Reusable iterator options shared by `each`, `forIn`, and `forOwn` */
    var eachIteratorOptions = {
      'args': 'collection, callback, thisArg',
      'top': "callback = callback && typeof thisArg == 'undefined' ? callback : baseCreateCallback(callback, thisArg, 3)",
      'array': "typeof length == 'number'",
      'keys': keys,
      'loop': 'if (callback(iterable[index], index, collection) === false) return result'
    };

    /** Reusable iterator options for `assign` and `defaults` */
    var defaultsIteratorOptions = {
      'args': 'object, source, guard',
      'top':
        'var args = arguments,\n' +
        '    argsIndex = 0,\n' +
        "    argsLength = typeof guard == 'number' ? 2 : args.length;\n" +
        'while (++argsIndex < argsLength) {\n' +
        '  iterable = args[argsIndex];\n' +
        '  if (iterable && objectTypes[typeof iterable]) {',
      'keys': keys,
      'loop': "if (typeof result[index] == 'undefined') result[index] = iterable[index]",
      'bottom': '  }\n}'
    };

    /** Reusable iterator options for `forIn` and `forOwn` */
    var forOwnIteratorOptions = {
      'top': 'if (!objectTypes[typeof iterable]) return result;\n' + eachIteratorOptions.top,
      'array': false
    };

    /**
     * Used to convert characters to HTML entities:
     *
     * Though the `>` character is escaped for symmetry, characters like `>` and `/`
     * don't require escaping in HTML and have no special meaning unless they're part
     * of a tag or an unquoted attribute value.
     * http://mathiasbynens.be/notes/ambiguous-ampersands (under "semi-related fun fact")
     */
    var htmlEscapes = {
      '&': '&amp;',
      '<': '&lt;',
      '>': '&gt;',
      '"': '&quot;',
      "'": '&#39;'
    };

    /** Used to convert HTML entities to characters */
    var htmlUnescapes = invert(htmlEscapes);

    /** Used to match HTML entities and HTML characters */
    var reEscapedHtml = RegExp('(' + keys(htmlUnescapes).join('|') + ')', 'g'),
        reUnescapedHtml = RegExp('[' + keys(htmlEscapes).join('') + ']', 'g');

    /**
     * A function compiled to iterate `arguments` objects, arrays, objects, and
     * strings consistenly across environments, executing the callback for each
     * element in the collection. The callback is bound to `thisArg` and invoked
     * with three arguments; (value, index|key, collection). Callbacks may exit
     * iteration early by explicitly returning `false`.
     *
     * @private
     * @type Function
     * @param {Array|Object|string} collection The collection to iterate over.
     * @param {Function} [callback=identity] The function called per iteration.
     * @param {*} [thisArg] The `this` binding of `callback`.
     * @returns {Array|Object|string} Returns `collection`.
     */
    var baseEach = createIterator(eachIteratorOptions);

    /*--------------------------------------------------------------------------*/

    /**
     * Assigns own enumerable properties of source object(s) to the destination
     * object. Subsequent sources will overwrite property assignments of previous
     * sources. If a callback is provided it will be executed to produce the
     * assigned values. The callback is bound to `thisArg` and invoked with two
     * arguments; (objectValue, sourceValue).
     *
     * @static
     * @memberOf _
     * @type Function
     * @alias extend
     * @category Objects
     * @param {Object} object The destination object.
     * @param {...Object} [source] The source objects.
     * @param {Function} [callback] The function to customize assigning values.
     * @param {*} [thisArg] The `this` binding of `callback`.
     * @returns {Object} Returns the destination object.
     * @example
     *
     * _.assign({ 'name': 'fred' }, { 'employer': 'slate' });
     * // => { 'name': 'fred', 'employer': 'slate' }
     *
     * var defaults = _.partialRight(_.assign, function(a, b) {
     *   return typeof a == 'undefined' ? b : a;
     * });
     *
     * var object = { 'name': 'barney' };
     * defaults(object, { 'name': 'fred', 'employer': 'slate' });
     * // => { 'name': 'barney', 'employer': 'slate' }
     */
    var assign = createIterator(defaultsIteratorOptions, {
      'top':
        defaultsIteratorOptions.top.replace(';',
          ';\n' +
          "if (argsLength > 3 && typeof args[argsLength - 2] == 'function') {\n" +
          '  var callback = baseCreateCallback(args[--argsLength - 1], args[argsLength--], 2);\n' +
          "} else if (argsLength > 2 && typeof args[argsLength - 1] == 'function') {\n" +
          '  callback = args[--argsLength];\n' +
          '}'
        ),
      'loop': 'result[index] = callback ? callback(result[index], iterable[index]) : iterable[index]'
    });

    /**
     * Creates a clone of `value`. If `isDeep` is `true` nested objects will also
     * be cloned, otherwise they will be assigned by reference. If a callback
     * is provided it will be executed to produce the cloned values. If the
     * callback returns `undefined` cloning will be handled by the method instead.
     * The callback is bound to `thisArg` and invoked with one argument; (value).
     *
     * @static
     * @memberOf _
     * @category Objects
     * @param {*} value The value to clone.
     * @param {boolean} [isDeep=false] Specify a deep clone.
     * @param {Function} [callback] The function to customize cloning values.
     * @param {*} [thisArg] The `this` binding of `callback`.
     * @returns {*} Returns the cloned value.
     * @example
     *
     * var characters = [
     *   { 'name': 'barney', 'age': 36 },
     *   { 'name': 'fred',   'age': 40 }
     * ];
     *
     * var shallow = _.clone(characters);
     * shallow[0] === characters[0];
     * // => true
     *
     * var deep = _.clone(characters, true);
     * deep[0] === characters[0];
     * // => false
     *
     * _.mixin({
     *   'clone': _.partialRight(_.clone, function(value) {
     *     return _.isElement(value) ? value.cloneNode(false) : undefined;
     *   })
     * });
     *
     * var clone = _.clone(document.body);
     * clone.childNodes.length;
     * // => 0
     */
    function clone(value, isDeep, callback, thisArg) {
      // allows working with "Collections" methods without using their `index`
      // and `collection` arguments for `isDeep` and `callback`
      if (typeof isDeep != 'boolean' && isDeep != null) {
        thisArg = callback;
        callback = isDeep;
        isDeep = false;
      }
      return baseClone(value, isDeep, typeof callback == 'function' && baseCreateCallback(callback, thisArg, 1));
    }

    /**
     * Creates a deep clone of `value`. If a callback is provided it will be
     * executed to produce the cloned values. If the callback returns `undefined`
     * cloning will be handled by the method instead. The callback is bound to
     * `thisArg` and invoked with one argument; (value).
     *
     * Note: This method is loosely based on the structured clone algorithm. Functions
     * and DOM nodes are **not** cloned. The enumerable properties of `arguments` objects and
     * objects created by constructors other than `Object` are cloned to plain `Object` objects.
     * See http://www.w3.org/TR/html5/infrastructure.html#internal-structured-cloning-algorithm.
     *
     * @static
     * @memberOf _
     * @category Objects
     * @param {*} value The value to deep clone.
     * @param {Function} [callback] The function to customize cloning values.
     * @param {*} [thisArg] The `this` binding of `callback`.
     * @returns {*} Returns the deep cloned value.
     * @example
     *
     * var characters = [
     *   { 'name': 'barney', 'age': 36 },
     *   { 'name': 'fred',   'age': 40 }
     * ];
     *
     * var deep = _.cloneDeep(characters);
     * deep[0] === characters[0];
     * // => false
     *
     * var view = {
     *   'label': 'docs',
     *   'node': element
     * };
     *
     * var clone = _.cloneDeep(view, function(value) {
     *   return _.isElement(value) ? value.cloneNode(true) : undefined;
     * });
     *
     * clone.node == view.node;
     * // => false
     */
    function cloneDeep(value, callback, thisArg) {
      return baseClone(value, true, typeof callback == 'function' && baseCreateCallback(callback, thisArg, 1));
    }

    /**
     * Creates an object that inherits from the given `prototype` object. If a
     * `properties` object is provided its own enumerable properties are assigned
     * to the created object.
     *
     * @static
     * @memberOf _
     * @category Objects
     * @param {Object} prototype The object to inherit from.
     * @param {Object} [properties] The properties to assign to the object.
     * @returns {Object} Returns the new object.
     * @example
     *
     * function Shape() {
     *   this.x = 0;
     *   this.y = 0;
     * }
     *
     * function Circle() {
     *   Shape.call(this);
     * }
     *
     * Circle.prototype = _.create(Shape.prototype, { 'constructor': Circle });
     *
     * var circle = new Circle;
     * circle instanceof Circle;
     * // => true
     *
     * circle instanceof Shape;
     * // => true
     */
    function create(prototype, properties) {
      var result = baseCreate(prototype);
      return properties ? assign(result, properties) : result;
    }

    /**
     * Assigns own enumerable properties of source object(s) to the destination
     * object for all destination properties that resolve to `undefined`. Once a
     * property is set, additional defaults of the same property will be ignored.
     *
     * @static
     * @memberOf _
     * @type Function
     * @category Objects
     * @param {Object} object The destination object.
     * @param {...Object} [source] The source objects.
     * @param- {Object} [guard] Allows working with `_.reduce` without using its
     *  `key` and `object` arguments as sources.
     * @returns {Object} Returns the destination object.
     * @example
     *
     * var object = { 'name': 'barney' };
     * _.defaults(object, { 'name': 'fred', 'employer': 'slate' });
     * // => { 'name': 'barney', 'employer': 'slate' }
     */
    var defaults = createIterator(defaultsIteratorOptions);

    /**
     * This method is like `_.findIndex` except that it returns the key of the
     * first element that passes the callback check, instead of the element itself.
     *
     * If a property name is provided for `callback` the created "_.pluck" style
     * callback will return the property value of the given element.
     *
     * If an object is provided for `callback` the created "_.where" style callback
     * will return `true` for elements that have the properties of the given object,
     * else `false`.
     *
     * @static
     * @memberOf _
     * @category Objects
     * @param {Object} object The object to search.
     * @param {Function|Object|string} [callback=identity] The function called per
     *  iteration. If a property name or object is provided it will be used to
     *  create a "_.pluck" or "_.where" style callback, respectively.
     * @param {*} [thisArg] The `this` binding of `callback`.
     * @returns {string|undefined} Returns the key of the found element, else `undefined`.
     * @example
     *
     * var characters = {
     *   'barney': {  'age': 36, 'blocked': false },
     *   'fred': {    'age': 40, 'blocked': true },
     *   'pebbles': { 'age': 1,  'blocked': false }
     * };
     *
     * _.findKey(characters, function(chr) {
     *   return chr.age < 40;
     * });
     * // => 'barney' (property order is not guaranteed across environments)
     *
     * // using "_.where" callback shorthand
     * _.findKey(characters, { 'age': 1 });
     * // => 'pebbles'
     *
     * // using "_.pluck" callback shorthand
     * _.findKey(characters, 'blocked');
     * // => 'fred'
     */
    function findKey(object, callback, thisArg) {
      var result;
      callback = lodash.createCallback(callback, thisArg, 3);
      forOwn(object, function(value, key, object) {
        if (callback(value, key, object)) {
          result = key;
          return false;
        }
      });
      return result;
    }

    /**
     * This method is like `_.findKey` except that it iterates over elements
     * of a `collection` in the opposite order.
     *
     * If a property name is provided for `callback` the created "_.pluck" style
     * callback will return the property value of the given element.
     *
     * If an object is provided for `callback` the created "_.where" style callback
     * will return `true` for elements that have the properties of the given object,
     * else `false`.
     *
     * @static
     * @memberOf _
     * @category Objects
     * @param {Object} object The object to search.
     * @param {Function|Object|string} [callback=identity] The function called per
     *  iteration. If a property name or object is provided it will be used to
     *  create a "_.pluck" or "_.where" style callback, respectively.
     * @param {*} [thisArg] The `this` binding of `callback`.
     * @returns {string|undefined} Returns the key of the found element, else `undefined`.
     * @example
     *
     * var characters = {
     *   'barney': {  'age': 36, 'blocked': true },
     *   'fred': {    'age': 40, 'blocked': false },
     *   'pebbles': { 'age': 1,  'blocked': true }
     * };
     *
     * _.findLastKey(characters, function(chr) {
     *   return chr.age < 40;
     * });
     * // => returns `pebbles`, assuming `_.findKey` returns `barney`
     *
     * // using "_.where" callback shorthand
     * _.findLastKey(characters, { 'age': 40 });
     * // => 'fred'
     *
     * // using "_.pluck" callback shorthand
     * _.findLastKey(characters, 'blocked');
     * // => 'pebbles'
     */
    function findLastKey(object, callback, thisArg) {
      var result;
      callback = lodash.createCallback(callback, thisArg, 3);
      forOwnRight(object, function(value, key, object) {
        if (callback(value, key, object)) {
          result = key;
          return false;
        }
      });
      return result;
    }

    /**
     * Iterates over own and inherited enumerable properties of an object,
     * executing the callback for each property. The callback is bound to `thisArg`
     * and invoked with three arguments; (value, key, object). Callbacks may exit
     * iteration early by explicitly returning `false`.
     *
     * @static
     * @memberOf _
     * @type Function
     * @category Objects
     * @param {Object} object The object to iterate over.
     * @param {Function} [callback=identity] The function called per iteration.
     * @param {*} [thisArg] The `this` binding of `callback`.
     * @returns {Object} Returns `object`.
     * @example
     *
     * function Shape() {
     *   this.x = 0;
     *   this.y = 0;
     * }
     *
     * Shape.prototype.move = function(x, y) {
     *   this.x += x;
     *   this.y += y;
     * };
     *
     * _.forIn(new Shape, function(value, key) {
     *   console.log(key);
     * });
     * // => logs 'x', 'y', and 'move' (property order is not guaranteed across environments)
     */
    var forIn = createIterator(eachIteratorOptions, forOwnIteratorOptions, {
      'useHas': false
    });

    /**
     * This method is like `_.forIn` except that it iterates over elements
     * of a `collection` in the opposite order.
     *
     * @static
     * @memberOf _
     * @category Objects
     * @param {Object} object The object to iterate over.
     * @param {Function} [callback=identity] The function called per iteration.
     * @param {*} [thisArg] The `this` binding of `callback`.
     * @returns {Object} Returns `object`.
     * @example
     *
     * function Shape() {
     *   this.x = 0;
     *   this.y = 0;
     * }
     *
     * Shape.prototype.move = function(x, y) {
     *   this.x += x;
     *   this.y += y;
     * };
     *
     * _.forInRight(new Shape, function(value, key) {
     *   console.log(key);
     * });
     * // => logs 'move', 'y', and 'x' assuming `_.forIn ` logs 'x', 'y', and 'move'
     */
    function forInRight(object, callback, thisArg) {
      var pairs = [];

      forIn(object, function(value, key) {
        pairs.push(key, value);
      });

      var length = pairs.length;
      callback = baseCreateCallback(callback, thisArg, 3);
      while (length--) {
        if (callback(pairs[length--], pairs[length], object) === false) {
          break;
        }
      }
      return object;
    }

    /**
     * Iterates over own enumerable properties of an object, executing the callback
     * for each property. The callback is bound to `thisArg` and invoked with three
     * arguments; (value, key, object). Callbacks may exit iteration early by
     * explicitly returning `false`.
     *
     * @static
     * @memberOf _
     * @type Function
     * @category Objects
     * @param {Object} object The object to iterate over.
     * @param {Function} [callback=identity] The function called per iteration.
     * @param {*} [thisArg] The `this` binding of `callback`.
     * @returns {Object} Returns `object`.
     * @example
     *
     * _.forOwn({ '0': 'zero', '1': 'one', 'length': 2 }, function(num, key) {
     *   console.log(key);
     * });
     * // => logs '0', '1', and 'length' (property order is not guaranteed across environments)
     */
    var forOwn = createIterator(eachIteratorOptions, forOwnIteratorOptions);

    /**
     * This method is like `_.forOwn` except that it iterates over elements
     * of a `collection` in the opposite order.
     *
     * @static
     * @memberOf _
     * @category Objects
     * @param {Object} object The object to iterate over.
     * @param {Function} [callback=identity] The function called per iteration.
     * @param {*} [thisArg] The `this` binding of `callback`.
     * @returns {Object} Returns `object`.
     * @example
     *
     * _.forOwnRight({ '0': 'zero', '1': 'one', 'length': 2 }, function(num, key) {
     *   console.log(key);
     * });
     * // => logs 'length', '1', and '0' assuming `_.forOwn` logs '0', '1', and 'length'
     */
    function forOwnRight(object, callback, thisArg) {
      var props = keys(object),
          length = props.length;

      callback = baseCreateCallback(callback, thisArg, 3);
      while (length--) {
        var key = props[length];
        if (callback(object[key], key, object) === false) {
          break;
        }
      }
      return object;
    }

    /**
     * Creates a sorted array of property names of all enumerable properties,
     * own and inherited, of `object` that have function values.
     *
     * @static
     * @memberOf _
     * @alias methods
     * @category Objects
     * @param {Object} object The object to inspect.
     * @returns {Array} Returns an array of property names that have function values.
     * @example
     *
     * _.functions(_);
     * // => ['all', 'any', 'bind', 'bindAll', 'clone', 'compact', 'compose', ...]
     */
    function functions(object) {
      var result = [];
      forIn(object, function(value, key) {
        if (isFunction(value)) {
          result.push(key);
        }
      });
      return result.sort();
    }

    /**
     * Checks if the specified property name exists as a direct property of `object`,
     * instead of an inherited property.
     *
     * @static
     * @memberOf _
     * @category Objects
     * @param {Object} object The object to inspect.
     * @param {string} key The name of the property to check.
     * @returns {boolean} Returns `true` if key is a direct property, else `false`.
     * @example
     *
     * _.has({ 'a': 1, 'b': 2, 'c': 3 }, 'b');
     * // => true
     */
    function has(object, key) {
      return object ? hasOwnProperty.call(object, key) : false;
    }

    /**
     * Creates an object composed of the inverted keys and values of the given object.
     *
     * @static
     * @memberOf _
     * @category Objects
     * @param {Object} object The object to invert.
     * @returns {Object} Returns the created inverted object.
     * @example
     *
     * _.invert({ 'first': 'fred', 'second': 'barney' });
     * // => { 'fred': 'first', 'barney': 'second' }
     */
    function invert(object) {
      var index = -1,
          props = keys(object),
          length = props.length,
          result = {};

      while (++index < length) {
        var key = props[index];
        result[object[key]] = key;
      }
      return result;
    }

    /**
     * Checks if `value` is a boolean value.
     *
     * @static
     * @memberOf _
     * @category Objects
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if the `value` is a boolean value, else `false`.
     * @example
     *
     * _.isBoolean(null);
     * // => false
     */
    function isBoolean(value) {
      return value === true || value === false ||
        value && typeof value == 'object' && toString.call(value) == boolClass || false;
    }

    /**
     * Checks if `value` is a date.
     *
     * @static
     * @memberOf _
     * @category Objects
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if the `value` is a date, else `false`.
     * @example
     *
     * _.isDate(new Date);
     * // => true
     */
    function isDate(value) {
      return value && typeof value == 'object' && toString.call(value) == dateClass || false;
    }

    /**
     * Checks if `value` is a DOM element.
     *
     * @static
     * @memberOf _
     * @category Objects
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if the `value` is a DOM element, else `false`.
     * @example
     *
     * _.isElement(document.body);
     * // => true
     */
    function isElement(value) {
      return value && value.nodeType === 1 || false;
    }

    /**
     * Checks if `value` is empty. Arrays, strings, or `arguments` objects with a
     * length of `0` and objects with no own enumerable properties are considered
     * "empty".
     *
     * @static
     * @memberOf _
     * @category Objects
     * @param {Array|Object|string} value The value to inspect.
     * @returns {boolean} Returns `true` if the `value` is empty, else `false`.
     * @example
     *
     * _.isEmpty([1, 2, 3]);
     * // => false
     *
     * _.isEmpty({});
     * // => true
     *
     * _.isEmpty('');
     * // => true
     */
    function isEmpty(value) {
      var result = true;
      if (!value) {
        return result;
      }
      var className = toString.call(value),
          length = value.length;

      if ((className == arrayClass || className == stringClass ||
          (support.argsClass ? className == argsClass : isArguments(value))) ||
          (className == objectClass && typeof length == 'number' && isFunction(value.splice))) {
        return !length;
      }
      forOwn(value, function() {
        return (result = false);
      });
      return result;
    }

    /**
     * Performs a deep comparison between two values to determine if they are
     * equivalent to each other. If a callback is provided it will be executed
     * to compare values. If the callback returns `undefined` comparisons will
     * be handled by the method instead. The callback is bound to `thisArg` and
     * invoked with two arguments; (a, b).
     *
     * @static
     * @memberOf _
     * @category Objects
     * @param {*} a The value to compare.
     * @param {*} b The other value to compare.
     * @param {Function} [callback] The function to customize comparing values.
     * @param {*} [thisArg] The `this` binding of `callback`.
     * @returns {boolean} Returns `true` if the values are equivalent, else `false`.
     * @example
     *
     * var object = { 'name': 'fred' };
     * var copy = { 'name': 'fred' };
     *
     * object == copy;
     * // => false
     *
     * _.isEqual(object, copy);
     * // => true
     *
     * var words = ['hello', 'goodbye'];
     * var otherWords = ['hi', 'goodbye'];
     *
     * _.isEqual(words, otherWords, function(a, b) {
     *   var reGreet = /^(?:hello|hi)$/i,
     *       aGreet = _.isString(a) && reGreet.test(a),
     *       bGreet = _.isString(b) && reGreet.test(b);
     *
     *   return (aGreet || bGreet) ? (aGreet == bGreet) : undefined;
     * });
     * // => true
     */
    function isEqual(a, b, callback, thisArg) {
      return baseIsEqual(a, b, typeof callback == 'function' && baseCreateCallback(callback, thisArg, 2));
    }

    /**
     * Checks if `value` is, or can be coerced to, a finite number.
     *
     * Note: This is not the same as native `isFinite` which will return true for
     * booleans and empty strings. See http://es5.github.io/#x15.1.2.5.
     *
     * @static
     * @memberOf _
     * @category Objects
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if the `value` is finite, else `false`.
     * @example
     *
     * _.isFinite(-101);
     * // => true
     *
     * _.isFinite('10');
     * // => true
     *
     * _.isFinite(true);
     * // => false
     *
     * _.isFinite('');
     * // => false
     *
     * _.isFinite(Infinity);
     * // => false
     */
    function isFinite(value) {
      return nativeIsFinite(value) && !nativeIsNaN(parseFloat(value));
    }

    /**
     * Checks if `value` is a function.
     *
     * @static
     * @memberOf _
     * @category Objects
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if the `value` is a function, else `false`.
     * @example
     *
     * _.isFunction(_);
     * // => true
     */
    function isFunction(value) {
      return typeof value == 'function';
    }
    // fallback for older versions of Chrome and Safari
    if (isFunction(/x/)) {
      isFunction = function(value) {
        return typeof value == 'function' && toString.call(value) == funcClass;
      };
    }

    /**
     * Checks if `value` is the language type of Object.
     * (e.g. arrays, functions, objects, regexes, `new Number(0)`, and `new String('')`)
     *
     * @static
     * @memberOf _
     * @category Objects
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if the `value` is an object, else `false`.
     * @example
     *
     * _.isObject({});
     * // => true
     *
     * _.isObject([1, 2, 3]);
     * // => true
     *
     * _.isObject(1);
     * // => false
     */
    function isObject(value) {
      // check if the value is the ECMAScript language type of Object
      // http://es5.github.io/#x8
      // and avoid a V8 bug
      // http://code.google.com/p/v8/issues/detail?id=2291
      return !!(value && objectTypes[typeof value]);
    }

    /**
     * Checks if `value` is `NaN`.
     *
     * Note: This is not the same as native `isNaN` which will return `true` for
     * `undefined` and other non-numeric values. See http://es5.github.io/#x15.1.2.4.
     *
     * @static
     * @memberOf _
     * @category Objects
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if the `value` is `NaN`, else `false`.
     * @example
     *
     * _.isNaN(NaN);
     * // => true
     *
     * _.isNaN(new Number(NaN));
     * // => true
     *
     * isNaN(undefined);
     * // => true
     *
     * _.isNaN(undefined);
     * // => false
     */
    function isNaN(value) {
      // `NaN` as a primitive is the only value that is not equal to itself
      // (perform the [[Class]] check first to avoid errors with some host objects in IE)
      return isNumber(value) && value != +value;
    }

    /**
     * Checks if `value` is `null`.
     *
     * @static
     * @memberOf _
     * @category Objects
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if the `value` is `null`, else `false`.
     * @example
     *
     * _.isNull(null);
     * // => true
     *
     * _.isNull(undefined);
     * // => false
     */
    function isNull(value) {
      return value === null;
    }

    /**
     * Checks if `value` is a number.
     *
     * Note: `NaN` is considered a number. See http://es5.github.io/#x8.5.
     *
     * @static
     * @memberOf _
     * @category Objects
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if the `value` is a number, else `false`.
     * @example
     *
     * _.isNumber(8.4 * 5);
     * // => true
     */
    function isNumber(value) {
      return typeof value == 'number' ||
        value && typeof value == 'object' && toString.call(value) == numberClass || false;
    }

    /**
     * Checks if `value` is an object created by the `Object` constructor.
     *
     * @static
     * @memberOf _
     * @category Objects
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if `value` is a plain object, else `false`.
     * @example
     *
     * function Shape() {
     *   this.x = 0;
     *   this.y = 0;
     * }
     *
     * _.isPlainObject(new Shape);
     * // => false
     *
     * _.isPlainObject([1, 2, 3]);
     * // => false
     *
     * _.isPlainObject({ 'x': 0, 'y': 0 });
     * // => true
     */
    var isPlainObject = !getPrototypeOf ? shimIsPlainObject : function(value) {
      if (!(value && toString.call(value) == objectClass) || (!support.argsClass && isArguments(value))) {
        return false;
      }
      var valueOf = value.valueOf,
          objProto = isNative(valueOf) && (objProto = getPrototypeOf(valueOf)) && getPrototypeOf(objProto);

      return objProto
        ? (value == objProto || getPrototypeOf(value) == objProto)
        : shimIsPlainObject(value);
    };

    /**
     * Checks if `value` is a regular expression.
     *
     * @static
     * @memberOf _
     * @category Objects
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if the `value` is a regular expression, else `false`.
     * @example
     *
     * _.isRegExp(/fred/);
     * // => true
     */
    function isRegExp(value) {
      return value && objectTypes[typeof value] && toString.call(value) == regexpClass || false;
    }

    /**
     * Checks if `value` is a string.
     *
     * @static
     * @memberOf _
     * @category Objects
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if the `value` is a string, else `false`.
     * @example
     *
     * _.isString('fred');
     * // => true
     */
    function isString(value) {
      return typeof value == 'string' ||
        value && typeof value == 'object' && toString.call(value) == stringClass || false;
    }

    /**
     * Checks if `value` is `undefined`.
     *
     * @static
     * @memberOf _
     * @category Objects
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if the `value` is `undefined`, else `false`.
     * @example
     *
     * _.isUndefined(void 0);
     * // => true
     */
    function isUndefined(value) {
      return typeof value == 'undefined';
    }

    /**
     * Creates an object with the same keys as `object` and values generated by
     * running each own enumerable property of `object` through the callback.
     * The callback is bound to `thisArg` and invoked with three arguments;
     * (value, key, object).
     *
     * If a property name is provided for `callback` the created "_.pluck" style
     * callback will return the property value of the given element.
     *
     * If an object is provided for `callback` the created "_.where" style callback
     * will return `true` for elements that have the properties of the given object,
     * else `false`.
     *
     * @static
     * @memberOf _
     * @category Objects
     * @param {Object} object The object to iterate over.
     * @param {Function|Object|string} [callback=identity] The function called
     *  per iteration. If a property name or object is provided it will be used
     *  to create a "_.pluck" or "_.where" style callback, respectively.
     * @param {*} [thisArg] The `this` binding of `callback`.
     * @returns {Array} Returns a new object with values of the results of each `callback` execution.
     * @example
     *
     * _.mapValues({ 'a': 1, 'b': 2, 'c': 3} , function(num) { return num * 3; });
     * // => { 'a': 3, 'b': 6, 'c': 9 }
     *
     * var characters = {
     *   'fred': { 'name': 'fred', 'age': 40 },
     *   'pebbles': { 'name': 'pebbles', 'age': 1 }
     * };
     *
     * // using "_.pluck" callback shorthand
     * _.mapValues(characters, 'age');
     * // => { 'fred': 40, 'pebbles': 1 }
     */
    function mapValues(object, callback, thisArg) {
      var result = {};
      callback = lodash.createCallback(callback, thisArg, 3);

      forOwn(object, function(value, key, object) {
        result[key] = callback(value, key, object);
      });
      return result;
    }

    /**
     * Recursively merges own enumerable properties of the source object(s), that
     * don't resolve to `undefined` into the destination object. Subsequent sources
     * will overwrite property assignments of previous sources. If a callback is
     * provided it will be executed to produce the merged values of the destination
     * and source properties. If the callback returns `undefined` merging will
     * be handled by the method instead. The callback is bound to `thisArg` and
     * invoked with two arguments; (objectValue, sourceValue).
     *
     * @static
     * @memberOf _
     * @category Objects
     * @param {Object} object The destination object.
     * @param {...Object} [source] The source objects.
     * @param {Function} [callback] The function to customize merging properties.
     * @param {*} [thisArg] The `this` binding of `callback`.
     * @returns {Object} Returns the destination object.
     * @example
     *
     * var names = {
     *   'characters': [
     *     { 'name': 'barney' },
     *     { 'name': 'fred' }
     *   ]
     * };
     *
     * var ages = {
     *   'characters': [
     *     { 'age': 36 },
     *     { 'age': 40 }
     *   ]
     * };
     *
     * _.merge(names, ages);
     * // => { 'characters': [{ 'name': 'barney', 'age': 36 }, { 'name': 'fred', 'age': 40 }] }
     *
     * var food = {
     *   'fruits': ['apple'],
     *   'vegetables': ['beet']
     * };
     *
     * var otherFood = {
     *   'fruits': ['banana'],
     *   'vegetables': ['carrot']
     * };
     *
     * _.merge(food, otherFood, function(a, b) {
     *   return _.isArray(a) ? a.concat(b) : undefined;
     * });
     * // => { 'fruits': ['apple', 'banana'], 'vegetables': ['beet', 'carrot] }
     */
    function merge(object) {
      var args = arguments,
          length = 2;

      if (!isObject(object)) {
        return object;
      }
      // allows working with `_.reduce` and `_.reduceRight` without using
      // their `index` and `collection` arguments
      if (typeof args[2] != 'number') {
        length = args.length;
      }
      if (length > 3 && typeof args[length - 2] == 'function') {
        var callback = baseCreateCallback(args[--length - 1], args[length--], 2);
      } else if (length > 2 && typeof args[length - 1] == 'function') {
        callback = args[--length];
      }
      var sources = slice(arguments, 1, length),
          index = -1,
          stackA = getArray(),
          stackB = getArray();

      while (++index < length) {
        baseMerge(object, sources[index], callback, stackA, stackB);
      }
      releaseArray(stackA);
      releaseArray(stackB);
      return object;
    }

    /**
     * Creates a shallow clone of `object` excluding the specified properties.
     * Property names may be specified as individual arguments or as arrays of
     * property names. If a callback is provided it will be executed for each
     * property of `object` omitting the properties the callback returns truey
     * for. The callback is bound to `thisArg` and invoked with three arguments;
     * (value, key, object).
     *
     * @static
     * @memberOf _
     * @category Objects
     * @param {Object} object The source object.
     * @param {Function|...string|string[]} [callback] The properties to omit or the
     *  function called per iteration.
     * @param {*} [thisArg] The `this` binding of `callback`.
     * @returns {Object} Returns an object without the omitted properties.
     * @example
     *
     * _.omit({ 'name': 'fred', 'age': 40 }, 'age');
     * // => { 'name': 'fred' }
     *
     * _.omit({ 'name': 'fred', 'age': 40 }, function(value) {
     *   return typeof value == 'number';
     * });
     * // => { 'name': 'fred' }
     */
    function omit(object, callback, thisArg) {
      var result = {};
      if (typeof callback != 'function') {
        var props = [];
        forIn(object, function(value, key) {
          props.push(key);
        });
        props = baseDifference(props, baseFlatten(arguments, true, false, 1));

        var index = -1,
            length = props.length;

        while (++index < length) {
          var key = props[index];
          result[key] = object[key];
        }
      } else {
        callback = lodash.createCallback(callback, thisArg, 3);
        forIn(object, function(value, key, object) {
          if (!callback(value, key, object)) {
            result[key] = value;
          }
        });
      }
      return result;
    }

    /**
     * Creates a two dimensional array of an object's key-value pairs,
     * i.e. `[[key1, value1], [key2, value2]]`.
     *
     * @static
     * @memberOf _
     * @category Objects
     * @param {Object} object The object to inspect.
     * @returns {Array} Returns new array of key-value pairs.
     * @example
     *
     * _.pairs({ 'barney': 36, 'fred': 40 });
     * // => [['barney', 36], ['fred', 40]] (property order is not guaranteed across environments)
     */
    function pairs(object) {
      var index = -1,
          props = keys(object),
          length = props.length,
          result = Array(length);

      while (++index < length) {
        var key = props[index];
        result[index] = [key, object[key]];
      }
      return result;
    }

    /**
     * Creates a shallow clone of `object` composed of the specified properties.
     * Property names may be specified as individual arguments or as arrays of
     * property names. If a callback is provided it will be executed for each
     * property of `object` picking the properties the callback returns truey
     * for. The callback is bound to `thisArg` and invoked with three arguments;
     * (value, key, object).
     *
     * @static
     * @memberOf _
     * @category Objects
     * @param {Object} object The source object.
     * @param {Function|...string|string[]} [callback] The function called per
     *  iteration or property names to pick, specified as individual property
     *  names or arrays of property names.
     * @param {*} [thisArg] The `this` binding of `callback`.
     * @returns {Object} Returns an object composed of the picked properties.
     * @example
     *
     * _.pick({ 'name': 'fred', '_userid': 'fred1' }, 'name');
     * // => { 'name': 'fred' }
     *
     * _.pick({ 'name': 'fred', '_userid': 'fred1' }, function(value, key) {
     *   return key.charAt(0) != '_';
     * });
     * // => { 'name': 'fred' }
     */
    function pick(object, callback, thisArg) {
      var result = {};
      if (typeof callback != 'function') {
        var index = -1,
            props = baseFlatten(arguments, true, false, 1),
            length = isObject(object) ? props.length : 0;

        while (++index < length) {
          var key = props[index];
          if (key in object) {
            result[key] = object[key];
          }
        }
      } else {
        callback = lodash.createCallback(callback, thisArg, 3);
        forIn(object, function(value, key, object) {
          if (callback(value, key, object)) {
            result[key] = value;
          }
        });
      }
      return result;
    }

    /**
     * An alternative to `_.reduce` this method transforms `object` to a new
     * `accumulator` object which is the result of running each of its own
     * enumerable properties through a callback, with each callback execution
     * potentially mutating the `accumulator` object. The callback is bound to
     * `thisArg` and invoked with four arguments; (accumulator, value, key, object).
     * Callbacks may exit iteration early by explicitly returning `false`.
     *
     * @static
     * @memberOf _
     * @category Objects
     * @param {Array|Object} object The object to iterate over.
     * @param {Function} [callback=identity] The function called per iteration.
     * @param {*} [accumulator] The custom accumulator value.
     * @param {*} [thisArg] The `this` binding of `callback`.
     * @returns {*} Returns the accumulated value.
     * @example
     *
     * var squares = _.transform([1, 2, 3, 4, 5, 6, 7, 8, 9, 10], function(result, num) {
     *   num *= num;
     *   if (num % 2) {
     *     return result.push(num) < 3;
     *   }
     * });
     * // => [1, 9, 25]
     *
     * var mapped = _.transform({ 'a': 1, 'b': 2, 'c': 3 }, function(result, num, key) {
     *   result[key] = num * 3;
     * });
     * // => { 'a': 3, 'b': 6, 'c': 9 }
     */
    function transform(object, callback, accumulator, thisArg) {
      var isArr = isArray(object);
      if (accumulator == null) {
        if (isArr) {
          accumulator = [];
        } else {
          var ctor = object && object.constructor,
              proto = ctor && ctor.prototype;

          accumulator = baseCreate(proto);
        }
      }
      if (callback) {
        callback = lodash.createCallback(callback, thisArg, 4);
        (isArr ? baseEach : forOwn)(object, function(value, index, object) {
          return callback(accumulator, value, index, object);
        });
      }
      return accumulator;
    }

    /**
     * Creates an array composed of the own enumerable property values of `object`.
     *
     * @static
     * @memberOf _
     * @category Objects
     * @param {Object} object The object to inspect.
     * @returns {Array} Returns an array of property values.
     * @example
     *
     * _.values({ 'one': 1, 'two': 2, 'three': 3 });
     * // => [1, 2, 3] (property order is not guaranteed across environments)
     */
    function values(object) {
      var index = -1,
          props = keys(object),
          length = props.length,
          result = Array(length);

      while (++index < length) {
        result[index] = object[props[index]];
      }
      return result;
    }

    /*--------------------------------------------------------------------------*/

    /**
     * Creates an array of elements from the specified indexes, or keys, of the
     * `collection`. Indexes may be specified as individual arguments or as arrays
     * of indexes.
     *
     * @static
     * @memberOf _
     * @category Collections
     * @param {Array|Object|string} collection The collection to iterate over.
     * @param {...(number|number[]|string|string[])} [index] The indexes of `collection`
     *   to retrieve, specified as individual indexes or arrays of indexes.
     * @returns {Array} Returns a new array of elements corresponding to the
     *  provided indexes.
     * @example
     *
     * _.at(['a', 'b', 'c', 'd', 'e'], [0, 2, 4]);
     * // => ['a', 'c', 'e']
     *
     * _.at(['fred', 'barney', 'pebbles'], 0, 2);
     * // => ['fred', 'pebbles']
     */
    function at(collection) {
      var args = arguments,
          index = -1,
          props = baseFlatten(args, true, false, 1),
          length = (args[2] && args[2][args[1]] === collection) ? 1 : props.length,
          result = Array(length);

      if (support.unindexedChars && isString(collection)) {
        collection = collection.split('');
      }
      while(++index < length) {
        result[index] = collection[props[index]];
      }
      return result;
    }

    /**
     * Checks if a given value is present in a collection using strict equality
     * for comparisons, i.e. `===`. If `fromIndex` is negative, it is used as the
     * offset from the end of the collection.
     *
     * @static
     * @memberOf _
     * @alias include
     * @category Collections
     * @param {Array|Object|string} collection The collection to iterate over.
     * @param {*} target The value to check for.
     * @param {number} [fromIndex=0] The index to search from.
     * @returns {boolean} Returns `true` if the `target` element is found, else `false`.
     * @example
     *
     * _.contains([1, 2, 3], 1);
     * // => true
     *
     * _.contains([1, 2, 3], 1, 2);
     * // => false
     *
     * _.contains({ 'name': 'fred', 'age': 40 }, 'fred');
     * // => true
     *
     * _.contains('pebbles', 'eb');
     * // => true
     */
    function contains(collection, target, fromIndex) {
      var index = -1,
          indexOf = getIndexOf(),
          length = collection ? collection.length : 0,
          result = false;

      fromIndex = (fromIndex < 0 ? nativeMax(0, length + fromIndex) : fromIndex) || 0;
      if (isArray(collection)) {
        result = indexOf(collection, target, fromIndex) > -1;
      } else if (typeof length == 'number') {
        result = (isString(collection) ? collection.indexOf(target, fromIndex) : indexOf(collection, target, fromIndex)) > -1;
      } else {
        baseEach(collection, function(value) {
          if (++index >= fromIndex) {
            return !(result = value === target);
          }
        });
      }
      return result;
    }

    /**
     * Creates an object composed of keys generated from the results of running
     * each element of `collection` through the callback. The corresponding value
     * of each key is the number of times the key was returned by the callback.
     * The callback is bound to `thisArg` and invoked with three arguments;
     * (value, index|key, collection).
     *
     * If a property name is provided for `callback` the created "_.pluck" style
     * callback will return the property value of the given element.
     *
     * If an object is provided for `callback` the created "_.where" style callback
     * will return `true` for elements that have the properties of the given object,
     * else `false`.
     *
     * @static
     * @memberOf _
     * @category Collections
     * @param {Array|Object|string} collection The collection to iterate over.
     * @param {Function|Object|string} [callback=identity] The function called
     *  per iteration. If a property name or object is provided it will be used
     *  to create a "_.pluck" or "_.where" style callback, respectively.
     * @param {*} [thisArg] The `this` binding of `callback`.
     * @returns {Object} Returns the composed aggregate object.
     * @example
     *
     * _.countBy([4.3, 6.1, 6.4], function(num) { return Math.floor(num); });
     * // => { '4': 1, '6': 2 }
     *
     * _.countBy([4.3, 6.1, 6.4], function(num) { return this.floor(num); }, Math);
     * // => { '4': 1, '6': 2 }
     *
     * _.countBy(['one', 'two', 'three'], 'length');
     * // => { '3': 2, '5': 1 }
     */
    var countBy = createAggregator(function(result, value, key) {
      (hasOwnProperty.call(result, key) ? result[key]++ : result[key] = 1);
    });

    /**
     * Checks if the given callback returns truey value for **all** elements of
     * a collection. The callback is bound to `thisArg` and invoked with three
     * arguments; (value, index|key, collection).
     *
     * If a property name is provided for `callback` the created "_.pluck" style
     * callback will return the property value of the given element.
     *
     * If an object is provided for `callback` the created "_.where" style callback
     * will return `true` for elements that have the properties of the given object,
     * else `false`.
     *
     * @static
     * @memberOf _
     * @alias all
     * @category Collections
     * @param {Array|Object|string} collection The collection to iterate over.
     * @param {Function|Object|string} [callback=identity] The function called
     *  per iteration. If a property name or object is provided it will be used
     *  to create a "_.pluck" or "_.where" style callback, respectively.
     * @param {*} [thisArg] The `this` binding of `callback`.
     * @returns {boolean} Returns `true` if all elements passed the callback check,
     *  else `false`.
     * @example
     *
     * _.every([true, 1, null, 'yes']);
     * // => false
     *
     * var characters = [
     *   { 'name': 'barney', 'age': 36 },
     *   { 'name': 'fred',   'age': 40 }
     * ];
     *
     * // using "_.pluck" callback shorthand
     * _.every(characters, 'age');
     * // => true
     *
     * // using "_.where" callback shorthand
     * _.every(characters, { 'age': 36 });
     * // => false
     */
    function every(collection, callback, thisArg) {
      var result = true;
      callback = lodash.createCallback(callback, thisArg, 3);

      if (isArray(collection)) {
        var index = -1,
            length = collection.length;

        while (++index < length) {
          if (!(result = !!callback(collection[index], index, collection))) {
            break;
          }
        }
      } else {
        baseEach(collection, function(value, index, collection) {
          return (result = !!callback(value, index, collection));
        });
      }
      return result;
    }

    /**
     * Iterates over elements of a collection, returning an array of all elements
     * the callback returns truey for. The callback is bound to `thisArg` and
     * invoked with three arguments; (value, index|key, collection).
     *
     * If a property name is provided for `callback` the created "_.pluck" style
     * callback will return the property value of the given element.
     *
     * If an object is provided for `callback` the created "_.where" style callback
     * will return `true` for elements that have the properties of the given object,
     * else `false`.
     *
     * @static
     * @memberOf _
     * @alias select
     * @category Collections
     * @param {Array|Object|string} collection The collection to iterate over.
     * @param {Function|Object|string} [callback=identity] The function called
     *  per iteration. If a property name or object is provided it will be used
     *  to create a "_.pluck" or "_.where" style callback, respectively.
     * @param {*} [thisArg] The `this` binding of `callback`.
     * @returns {Array} Returns a new array of elements that passed the callback check.
     * @example
     *
     * var evens = _.filter([1, 2, 3, 4, 5, 6], function(num) { return num % 2 == 0; });
     * // => [2, 4, 6]
     *
     * var characters = [
     *   { 'name': 'barney', 'age': 36, 'blocked': false },
     *   { 'name': 'fred',   'age': 40, 'blocked': true }
     * ];
     *
     * // using "_.pluck" callback shorthand
     * _.filter(characters, 'blocked');
     * // => [{ 'name': 'fred', 'age': 40, 'blocked': true }]
     *
     * // using "_.where" callback shorthand
     * _.filter(characters, { 'age': 36 });
     * // => [{ 'name': 'barney', 'age': 36, 'blocked': false }]
     */
    function filter(collection, callback, thisArg) {
      var result = [];
      callback = lodash.createCallback(callback, thisArg, 3);

      if (isArray(collection)) {
        var index = -1,
            length = collection.length;

        while (++index < length) {
          var value = collection[index];
          if (callback(value, index, collection)) {
            result.push(value);
          }
        }
      } else {
        baseEach(collection, function(value, index, collection) {
          if (callback(value, index, collection)) {
            result.push(value);
          }
        });
      }
      return result;
    }

    /**
     * Iterates over elements of a collection, returning the first element that
     * the callback returns truey for. The callback is bound to `thisArg` and
     * invoked with three arguments; (value, index|key, collection).
     *
     * If a property name is provided for `callback` the created "_.pluck" style
     * callback will return the property value of the given element.
     *
     * If an object is provided for `callback` the created "_.where" style callback
     * will return `true` for elements that have the properties of the given object,
     * else `false`.
     *
     * @static
     * @memberOf _
     * @alias detect, findWhere
     * @category Collections
     * @param {Array|Object|string} collection The collection to iterate over.
     * @param {Function|Object|string} [callback=identity] The function called
     *  per iteration. If a property name or object is provided it will be used
     *  to create a "_.pluck" or "_.where" style callback, respectively.
     * @param {*} [thisArg] The `this` binding of `callback`.
     * @returns {*} Returns the found element, else `undefined`.
     * @example
     *
     * var characters = [
     *   { 'name': 'barney',  'age': 36, 'blocked': false },
     *   { 'name': 'fred',    'age': 40, 'blocked': true },
     *   { 'name': 'pebbles', 'age': 1,  'blocked': false }
     * ];
     *
     * _.find(characters, function(chr) {
     *   return chr.age < 40;
     * });
     * // => { 'name': 'barney', 'age': 36, 'blocked': false }
     *
     * // using "_.where" callback shorthand
     * _.find(characters, { 'age': 1 });
     * // =>  { 'name': 'pebbles', 'age': 1, 'blocked': false }
     *
     * // using "_.pluck" callback shorthand
     * _.find(characters, 'blocked');
     * // => { 'name': 'fred', 'age': 40, 'blocked': true }
     */
    function find(collection, callback, thisArg) {
      callback = lodash.createCallback(callback, thisArg, 3);

      if (isArray(collection)) {
        var index = -1,
            length = collection.length;

        while (++index < length) {
          var value = collection[index];
          if (callback(value, index, collection)) {
            return value;
          }
        }
      } else {
        var result;
        baseEach(collection, function(value, index, collection) {
          if (callback(value, index, collection)) {
            result = value;
            return false;
          }
        });
        return result;
      }
    }

    /**
     * This method is like `_.find` except that it iterates over elements
     * of a `collection` from right to left.
     *
     * @static
     * @memberOf _
     * @category Collections
     * @param {Array|Object|string} collection The collection to iterate over.
     * @param {Function|Object|string} [callback=identity] The function called
     *  per iteration. If a property name or object is provided it will be used
     *  to create a "_.pluck" or "_.where" style callback, respectively.
     * @param {*} [thisArg] The `this` binding of `callback`.
     * @returns {*} Returns the found element, else `undefined`.
     * @example
     *
     * _.findLast([1, 2, 3, 4], function(num) {
     *   return num % 2 == 1;
     * });
     * // => 3
     */
    function findLast(collection, callback, thisArg) {
      var result;
      callback = lodash.createCallback(callback, thisArg, 3);
      forEachRight(collection, function(value, index, collection) {
        if (callback(value, index, collection)) {
          result = value;
          return false;
        }
      });
      return result;
    }

    /**
     * Iterates over elements of a collection, executing the callback for each
     * element. The callback is bound to `thisArg` and invoked with three arguments;
     * (value, index|key, collection). Callbacks may exit iteration early by
     * explicitly returning `false`.
     *
     * Note: As with other "Collections" methods, objects with a `length` property
     * are iterated like arrays. To avoid this behavior `_.forIn` or `_.forOwn`
     * may be used for object iteration.
     *
     * @static
     * @memberOf _
     * @alias each
     * @category Collections
     * @param {Array|Object|string} collection The collection to iterate over.
     * @param {Function} [callback=identity] The function called per iteration.
     * @param {*} [thisArg] The `this` binding of `callback`.
     * @returns {Array|Object|string} Returns `collection`.
     * @example
     *
     * _([1, 2, 3]).forEach(function(num) { console.log(num); }).join(',');
     * // => logs each number and returns '1,2,3'
     *
     * _.forEach({ 'one': 1, 'two': 2, 'three': 3 }, function(num) { console.log(num); });
     * // => logs each number and returns the object (property order is not guaranteed across environments)
     */
    function forEach(collection, callback, thisArg) {
      if (callback && typeof thisArg == 'undefined' && isArray(collection)) {
        var index = -1,
            length = collection.length;

        while (++index < length) {
          if (callback(collection[index], index, collection) === false) {
            break;
          }
        }
      } else {
        baseEach(collection, callback, thisArg);
      }
      return collection;
    }

    /**
     * This method is like `_.forEach` except that it iterates over elements
     * of a `collection` from right to left.
     *
     * @static
     * @memberOf _
     * @alias eachRight
     * @category Collections
     * @param {Array|Object|string} collection The collection to iterate over.
     * @param {Function} [callback=identity] The function called per iteration.
     * @param {*} [thisArg] The `this` binding of `callback`.
     * @returns {Array|Object|string} Returns `collection`.
     * @example
     *
     * _([1, 2, 3]).forEachRight(function(num) { console.log(num); }).join(',');
     * // => logs each number from right to left and returns '3,2,1'
     */
    function forEachRight(collection, callback, thisArg) {
      var iterable = collection,
          length = collection ? collection.length : 0;

      callback = callback && typeof thisArg == 'undefined' ? callback : baseCreateCallback(callback, thisArg, 3);
      if (isArray(collection)) {
        while (length--) {
          if (callback(collection[length], length, collection) === false) {
            break;
          }
        }
      } else {
        if (typeof length != 'number') {
          var props = keys(collection);
          length = props.length;
        } else if (support.unindexedChars && isString(collection)) {
          iterable = collection.split('');
        }
        baseEach(collection, function(value, key, collection) {
          key = props ? props[--length] : --length;
          return callback(iterable[key], key, collection);
        });
      }
      return collection;
    }

    /**
     * Creates an object composed of keys generated from the results of running
     * each element of a collection through the callback. The corresponding value
     * of each key is an array of the elements responsible for generating the key.
     * The callback is bound to `thisArg` and invoked with three arguments;
     * (value, index|key, collection).
     *
     * If a property name is provided for `callback` the created "_.pluck" style
     * callback will return the property value of the given element.
     *
     * If an object is provided for `callback` the created "_.where" style callback
     * will return `true` for elements that have the properties of the given object,
     * else `false`
     *
     * @static
     * @memberOf _
     * @category Collections
     * @param {Array|Object|string} collection The collection to iterate over.
     * @param {Function|Object|string} [callback=identity] The function called
     *  per iteration. If a property name or object is provided it will be used
     *  to create a "_.pluck" or "_.where" style callback, respectively.
     * @param {*} [thisArg] The `this` binding of `callback`.
     * @returns {Object} Returns the composed aggregate object.
     * @example
     *
     * _.groupBy([4.2, 6.1, 6.4], function(num) { return Math.floor(num); });
     * // => { '4': [4.2], '6': [6.1, 6.4] }
     *
     * _.groupBy([4.2, 6.1, 6.4], function(num) { return this.floor(num); }, Math);
     * // => { '4': [4.2], '6': [6.1, 6.4] }
     *
     * // using "_.pluck" callback shorthand
     * _.groupBy(['one', 'two', 'three'], 'length');
     * // => { '3': ['one', 'two'], '5': ['three'] }
     */
    var groupBy = createAggregator(function(result, value, key) {
      (hasOwnProperty.call(result, key) ? result[key] : result[key] = []).push(value);
    });

    /**
     * Creates an object composed of keys generated from the results of running
     * each element of the collection through the given callback. The corresponding
     * value of each key is the last element responsible for generating the key.
     * The callback is bound to `thisArg` and invoked with three arguments;
     * (value, index|key, collection).
     *
     * If a property name is provided for `callback` the created "_.pluck" style
     * callback will return the property value of the given element.
     *
     * If an object is provided for `callback` the created "_.where" style callback
     * will return `true` for elements that have the properties of the given object,
     * else `false`.
     *
     * @static
     * @memberOf _
     * @category Collections
     * @param {Array|Object|string} collection The collection to iterate over.
     * @param {Function|Object|string} [callback=identity] The function called
     *  per iteration. If a property name or object is provided it will be used
     *  to create a "_.pluck" or "_.where" style callback, respectively.
     * @param {*} [thisArg] The `this` binding of `callback`.
     * @returns {Object} Returns the composed aggregate object.
     * @example
     *
     * var keys = [
     *   { 'dir': 'left', 'code': 97 },
     *   { 'dir': 'right', 'code': 100 }
     * ];
     *
     * _.indexBy(keys, 'dir');
     * // => { 'left': { 'dir': 'left', 'code': 97 }, 'right': { 'dir': 'right', 'code': 100 } }
     *
     * _.indexBy(keys, function(key) { return String.fromCharCode(key.code); });
     * // => { 'a': { 'dir': 'left', 'code': 97 }, 'd': { 'dir': 'right', 'code': 100 } }
     *
     * _.indexBy(characters, function(key) { this.fromCharCode(key.code); }, String);
     * // => { 'a': { 'dir': 'left', 'code': 97 }, 'd': { 'dir': 'right', 'code': 100 } }
     */
    var indexBy = createAggregator(function(result, value, key) {
      result[key] = value;
    });

    /**
     * Invokes the method named by `methodName` on each element in the `collection`
     * returning an array of the results of each invoked method. Additional arguments
     * will be provided to each invoked method. If `methodName` is a function it
     * will be invoked for, and `this` bound to, each element in the `collection`.
     *
     * @static
     * @memberOf _
     * @category Collections
     * @param {Array|Object|string} collection The collection to iterate over.
     * @param {Function|string} methodName The name of the method to invoke or
     *  the function invoked per iteration.
     * @param {...*} [arg] Arguments to invoke the method with.
     * @returns {Array} Returns a new array of the results of each invoked method.
     * @example
     *
     * _.invoke([[5, 1, 7], [3, 2, 1]], 'sort');
     * // => [[1, 5, 7], [1, 2, 3]]
     *
     * _.invoke([123, 456], String.prototype.split, '');
     * // => [['1', '2', '3'], ['4', '5', '6']]
     */
    function invoke(collection, methodName) {
      var args = slice(arguments, 2),
          index = -1,
          isFunc = typeof methodName == 'function',
          length = collection ? collection.length : 0,
          result = Array(typeof length == 'number' ? length : 0);

      forEach(collection, function(value) {
        result[++index] = (isFunc ? methodName : value[methodName]).apply(value, args);
      });
      return result;
    }

    /**
     * Creates an array of values by running each element in the collection
     * through the callback. The callback is bound to `thisArg` and invoked with
     * three arguments; (value, index|key, collection).
     *
     * If a property name is provided for `callback` the created "_.pluck" style
     * callback will return the property value of the given element.
     *
     * If an object is provided for `callback` the created "_.where" style callback
     * will return `true` for elements that have the properties of the given object,
     * else `false`.
     *
     * @static
     * @memberOf _
     * @alias collect
     * @category Collections
     * @param {Array|Object|string} collection The collection to iterate over.
     * @param {Function|Object|string} [callback=identity] The function called
     *  per iteration. If a property name or object is provided it will be used
     *  to create a "_.pluck" or "_.where" style callback, respectively.
     * @param {*} [thisArg] The `this` binding of `callback`.
     * @returns {Array} Returns a new array of the results of each `callback` execution.
     * @example
     *
     * _.map([1, 2, 3], function(num) { return num * 3; });
     * // => [3, 6, 9]
     *
     * _.map({ 'one': 1, 'two': 2, 'three': 3 }, function(num) { return num * 3; });
     * // => [3, 6, 9] (property order is not guaranteed across environments)
     *
     * var characters = [
     *   { 'name': 'barney', 'age': 36 },
     *   { 'name': 'fred',   'age': 40 }
     * ];
     *
     * // using "_.pluck" callback shorthand
     * _.map(characters, 'name');
     * // => ['barney', 'fred']
     */
    function map(collection, callback, thisArg) {
      var index = -1,
          length = collection ? collection.length : 0,
          result = Array(typeof length == 'number' ? length : 0);

      callback = lodash.createCallback(callback, thisArg, 3);
      if (isArray(collection)) {
        while (++index < length) {
          result[index] = callback(collection[index], index, collection);
        }
      } else {
        baseEach(collection, function(value, key, collection) {
          result[++index] = callback(value, key, collection);
        });
      }
      return result;
    }

    /**
     * Retrieves the maximum value of a collection. If the collection is empty or
     * falsey `-Infinity` is returned. If a callback is provided it will be executed
     * for each value in the collection to generate the criterion by which the value
     * is ranked. The callback is bound to `thisArg` and invoked with three
     * arguments; (value, index, collection).
     *
     * If a property name is provided for `callback` the created "_.pluck" style
     * callback will return the property value of the given element.
     *
     * If an object is provided for `callback` the created "_.where" style callback
     * will return `true` for elements that have the properties of the given object,
     * else `false`.
     *
     * @static
     * @memberOf _
     * @category Collections
     * @param {Array|Object|string} collection The collection to iterate over.
     * @param {Function|Object|string} [callback=identity] The function called
     *  per iteration. If a property name or object is provided it will be used
     *  to create a "_.pluck" or "_.where" style callback, respectively.
     * @param {*} [thisArg] The `this` binding of `callback`.
     * @returns {*} Returns the maximum value.
     * @example
     *
     * _.max([4, 2, 8, 6]);
     * // => 8
     *
     * var characters = [
     *   { 'name': 'barney', 'age': 36 },
     *   { 'name': 'fred',   'age': 40 }
     * ];
     *
     * _.max(characters, function(chr) { return chr.age; });
     * // => { 'name': 'fred', 'age': 40 };
     *
     * // using "_.pluck" callback shorthand
     * _.max(characters, 'age');
     * // => { 'name': 'fred', 'age': 40 };
     */
    function max(collection, callback, thisArg) {
      var computed = -Infinity,
          result = computed;

      // allows working with functions like `_.map` without using
      // their `index` argument as a callback
      if (typeof callback != 'function' && thisArg && thisArg[callback] === collection) {
        callback = null;
      }
      if (callback == null && isArray(collection)) {
        var index = -1,
            length = collection.length;

        while (++index < length) {
          var value = collection[index];
          if (value > result) {
            result = value;
          }
        }
      } else {
        callback = (callback == null && isString(collection))
          ? charAtCallback
          : lodash.createCallback(callback, thisArg, 3);

        baseEach(collection, function(value, index, collection) {
          var current = callback(value, index, collection);
          if (current > computed) {
            computed = current;
            result = value;
          }
        });
      }
      return result;
    }

    /**
     * Retrieves the minimum value of a collection. If the collection is empty or
     * falsey `Infinity` is returned. If a callback is provided it will be executed
     * for each value in the collection to generate the criterion by which the value
     * is ranked. The callback is bound to `thisArg` and invoked with three
     * arguments; (value, index, collection).
     *
     * If a property name is provided for `callback` the created "_.pluck" style
     * callback will return the property value of the given element.
     *
     * If an object is provided for `callback` the created "_.where" style callback
     * will return `true` for elements that have the properties of the given object,
     * else `false`.
     *
     * @static
     * @memberOf _
     * @category Collections
     * @param {Array|Object|string} collection The collection to iterate over.
     * @param {Function|Object|string} [callback=identity] The function called
     *  per iteration. If a property name or object is provided it will be used
     *  to create a "_.pluck" or "_.where" style callback, respectively.
     * @param {*} [thisArg] The `this` binding of `callback`.
     * @returns {*} Returns the minimum value.
     * @example
     *
     * _.min([4, 2, 8, 6]);
     * // => 2
     *
     * var characters = [
     *   { 'name': 'barney', 'age': 36 },
     *   { 'name': 'fred',   'age': 40 }
     * ];
     *
     * _.min(characters, function(chr) { return chr.age; });
     * // => { 'name': 'barney', 'age': 36 };
     *
     * // using "_.pluck" callback shorthand
     * _.min(characters, 'age');
     * // => { 'name': 'barney', 'age': 36 };
     */
    function min(collection, callback, thisArg) {
      var computed = Infinity,
          result = computed;

      // allows working with functions like `_.map` without using
      // their `index` argument as a callback
      if (typeof callback != 'function' && thisArg && thisArg[callback] === collection) {
        callback = null;
      }
      if (callback == null && isArray(collection)) {
        var index = -1,
            length = collection.length;

        while (++index < length) {
          var value = collection[index];
          if (value < result) {
            result = value;
          }
        }
      } else {
        callback = (callback == null && isString(collection))
          ? charAtCallback
          : lodash.createCallback(callback, thisArg, 3);

        baseEach(collection, function(value, index, collection) {
          var current = callback(value, index, collection);
          if (current < computed) {
            computed = current;
            result = value;
          }
        });
      }
      return result;
    }

    /**
     * Retrieves the value of a specified property from all elements in the collection.
     *
     * @static
     * @memberOf _
     * @type Function
     * @category Collections
     * @param {Array|Object|string} collection The collection to iterate over.
     * @param {string} property The name of the property to pluck.
     * @returns {Array} Returns a new array of property values.
     * @example
     *
     * var characters = [
     *   { 'name': 'barney', 'age': 36 },
     *   { 'name': 'fred',   'age': 40 }
     * ];
     *
     * _.pluck(characters, 'name');
     * // => ['barney', 'fred']
     */
    var pluck = map;

    /**
     * Reduces a collection to a value which is the accumulated result of running
     * each element in the collection through the callback, where each successive
     * callback execution consumes the return value of the previous execution. If
     * `accumulator` is not provided the first element of the collection will be
     * used as the initial `accumulator` value. The callback is bound to `thisArg`
     * and invoked with four arguments; (accumulator, value, index|key, collection).
     *
     * @static
     * @memberOf _
     * @alias foldl, inject
     * @category Collections
     * @param {Array|Object|string} collection The collection to iterate over.
     * @param {Function} [callback=identity] The function called per iteration.
     * @param {*} [accumulator] Initial value of the accumulator.
     * @param {*} [thisArg] The `this` binding of `callback`.
     * @returns {*} Returns the accumulated value.
     * @example
     *
     * var sum = _.reduce([1, 2, 3], function(sum, num) {
     *   return sum + num;
     * });
     * // => 6
     *
     * var mapped = _.reduce({ 'a': 1, 'b': 2, 'c': 3 }, function(result, num, key) {
     *   result[key] = num * 3;
     *   return result;
     * }, {});
     * // => { 'a': 3, 'b': 6, 'c': 9 }
     */
    function reduce(collection, callback, accumulator, thisArg) {
      var noaccum = arguments.length < 3;
      callback = lodash.createCallback(callback, thisArg, 4);

      if (isArray(collection)) {
        var index = -1,
            length = collection.length;

        if (noaccum) {
          accumulator = collection[++index];
        }
        while (++index < length) {
          accumulator = callback(accumulator, collection[index], index, collection);
        }
      } else {
        baseEach(collection, function(value, index, collection) {
          accumulator = noaccum
            ? (noaccum = false, value)
            : callback(accumulator, value, index, collection)
        });
      }
      return accumulator;
    }

    /**
     * This method is like `_.reduce` except that it iterates over elements
     * of a `collection` from right to left.
     *
     * @static
     * @memberOf _
     * @alias foldr
     * @category Collections
     * @param {Array|Object|string} collection The collection to iterate over.
     * @param {Function} [callback=identity] The function called per iteration.
     * @param {*} [accumulator] Initial value of the accumulator.
     * @param {*} [thisArg] The `this` binding of `callback`.
     * @returns {*} Returns the accumulated value.
     * @example
     *
     * var list = [[0, 1], [2, 3], [4, 5]];
     * var flat = _.reduceRight(list, function(a, b) { return a.concat(b); }, []);
     * // => [4, 5, 2, 3, 0, 1]
     */
    function reduceRight(collection, callback, accumulator, thisArg) {
      var noaccum = arguments.length < 3;
      callback = lodash.createCallback(callback, thisArg, 4);
      forEachRight(collection, function(value, index, collection) {
        accumulator = noaccum
          ? (noaccum = false, value)
          : callback(accumulator, value, index, collection);
      });
      return accumulator;
    }

    /**
     * The opposite of `_.filter` this method returns the elements of a
     * collection that the callback does **not** return truey for.
     *
     * If a property name is provided for `callback` the created "_.pluck" style
     * callback will return the property value of the given element.
     *
     * If an object is provided for `callback` the created "_.where" style callback
     * will return `true` for elements that have the properties of the given object,
     * else `false`.
     *
     * @static
     * @memberOf _
     * @category Collections
     * @param {Array|Object|string} collection The collection to iterate over.
     * @param {Function|Object|string} [callback=identity] The function called
     *  per iteration. If a property name or object is provided it will be used
     *  to create a "_.pluck" or "_.where" style callback, respectively.
     * @param {*} [thisArg] The `this` binding of `callback`.
     * @returns {Array} Returns a new array of elements that failed the callback check.
     * @example
     *
     * var odds = _.reject([1, 2, 3, 4, 5, 6], function(num) { return num % 2 == 0; });
     * // => [1, 3, 5]
     *
     * var characters = [
     *   { 'name': 'barney', 'age': 36, 'blocked': false },
     *   { 'name': 'fred',   'age': 40, 'blocked': true }
     * ];
     *
     * // using "_.pluck" callback shorthand
     * _.reject(characters, 'blocked');
     * // => [{ 'name': 'barney', 'age': 36, 'blocked': false }]
     *
     * // using "_.where" callback shorthand
     * _.reject(characters, { 'age': 36 });
     * // => [{ 'name': 'fred', 'age': 40, 'blocked': true }]
     */
    function reject(collection, callback, thisArg) {
      callback = lodash.createCallback(callback, thisArg, 3);
      return filter(collection, function(value, index, collection) {
        return !callback(value, index, collection);
      });
    }

    /**
     * Retrieves a random element or `n` random elements from a collection.
     *
     * @static
     * @memberOf _
     * @category Collections
     * @param {Array|Object|string} collection The collection to sample.
     * @param {number} [n] The number of elements to sample.
     * @param- {Object} [guard] Allows working with functions like `_.map`
     *  without using their `index` arguments as `n`.
     * @returns {Array} Returns the random sample(s) of `collection`.
     * @example
     *
     * _.sample([1, 2, 3, 4]);
     * // => 2
     *
     * _.sample([1, 2, 3, 4], 2);
     * // => [3, 1]
     */
    function sample(collection, n, guard) {
      if (collection && typeof collection.length != 'number') {
        collection = values(collection);
      } else if (support.unindexedChars && isString(collection)) {
        collection = collection.split('');
      }
      if (n == null || guard) {
        return collection ? collection[baseRandom(0, collection.length - 1)] : undefined;
      }
      var result = shuffle(collection);
      result.length = nativeMin(nativeMax(0, n), result.length);
      return result;
    }

    /**
     * Creates an array of shuffled values, using a version of the Fisher-Yates
     * shuffle. See http://en.wikipedia.org/wiki/Fisher-Yates_shuffle.
     *
     * @static
     * @memberOf _
     * @category Collections
     * @param {Array|Object|string} collection The collection to shuffle.
     * @returns {Array} Returns a new shuffled collection.
     * @example
     *
     * _.shuffle([1, 2, 3, 4, 5, 6]);
     * // => [4, 1, 6, 3, 5, 2]
     */
    function shuffle(collection) {
      var index = -1,
          length = collection ? collection.length : 0,
          result = Array(typeof length == 'number' ? length : 0);

      forEach(collection, function(value) {
        var rand = baseRandom(0, ++index);
        result[index] = result[rand];
        result[rand] = value;
      });
      return result;
    }

    /**
     * Gets the size of the `collection` by returning `collection.length` for arrays
     * and array-like objects or the number of own enumerable properties for objects.
     *
     * @static
     * @memberOf _
     * @category Collections
     * @param {Array|Object|string} collection The collection to inspect.
     * @returns {number} Returns `collection.length` or number of own enumerable properties.
     * @example
     *
     * _.size([1, 2]);
     * // => 2
     *
     * _.size({ 'one': 1, 'two': 2, 'three': 3 });
     * // => 3
     *
     * _.size('pebbles');
     * // => 7
     */
    function size(collection) {
      var length = collection ? collection.length : 0;
      return typeof length == 'number' ? length : keys(collection).length;
    }

    /**
     * Checks if the callback returns a truey value for **any** element of a
     * collection. The function returns as soon as it finds a passing value and
     * does not iterate over the entire collection. The callback is bound to
     * `thisArg` and invoked with three arguments; (value, index|key, collection).
     *
     * If a property name is provided for `callback` the created "_.pluck" style
     * callback will return the property value of the given element.
     *
     * If an object is provided for `callback` the created "_.where" style callback
     * will return `true` for elements that have the properties of the given object,
     * else `false`.
     *
     * @static
     * @memberOf _
     * @alias any
     * @category Collections
     * @param {Array|Object|string} collection The collection to iterate over.
     * @param {Function|Object|string} [callback=identity] The function called
     *  per iteration. If a property name or object is provided it will be used
     *  to create a "_.pluck" or "_.where" style callback, respectively.
     * @param {*} [thisArg] The `this` binding of `callback`.
     * @returns {boolean} Returns `true` if any element passed the callback check,
     *  else `false`.
     * @example
     *
     * _.some([null, 0, 'yes', false], Boolean);
     * // => true
     *
     * var characters = [
     *   { 'name': 'barney', 'age': 36, 'blocked': false },
     *   { 'name': 'fred',   'age': 40, 'blocked': true }
     * ];
     *
     * // using "_.pluck" callback shorthand
     * _.some(characters, 'blocked');
     * // => true
     *
     * // using "_.where" callback shorthand
     * _.some(characters, { 'age': 1 });
     * // => false
     */
    function some(collection, callback, thisArg) {
      var result;
      callback = lodash.createCallback(callback, thisArg, 3);

      if (isArray(collection)) {
        var index = -1,
            length = collection.length;

        while (++index < length) {
          if ((result = callback(collection[index], index, collection))) {
            break;
          }
        }
      } else {
        baseEach(collection, function(value, index, collection) {
          return !(result = callback(value, index, collection));
        });
      }
      return !!result;
    }

    /**
     * Creates an array of elements, sorted in ascending order by the results of
     * running each element in a collection through the callback. This method
     * performs a stable sort, that is, it will preserve the original sort order
     * of equal elements. The callback is bound to `thisArg` and invoked with
     * three arguments; (value, index|key, collection).
     *
     * If a property name is provided for `callback` the created "_.pluck" style
     * callback will return the property value of the given element.
     *
     * If an array of property names is provided for `callback` the collection
     * will be sorted by each property value.
     *
     * If an object is provided for `callback` the created "_.where" style callback
     * will return `true` for elements that have the properties of the given object,
     * else `false`.
     *
     * @static
     * @memberOf _
     * @category Collections
     * @param {Array|Object|string} collection The collection to iterate over.
     * @param {Array|Function|Object|string} [callback=identity] The function called
     *  per iteration. If a property name or object is provided it will be used
     *  to create a "_.pluck" or "_.where" style callback, respectively.
     * @param {*} [thisArg] The `this` binding of `callback`.
     * @returns {Array} Returns a new array of sorted elements.
     * @example
     *
     * _.sortBy([1, 2, 3], function(num) { return Math.sin(num); });
     * // => [3, 1, 2]
     *
     * _.sortBy([1, 2, 3], function(num) { return this.sin(num); }, Math);
     * // => [3, 1, 2]
     *
     * var characters = [
     *   { 'name': 'barney',  'age': 36 },
     *   { 'name': 'fred',    'age': 40 },
     *   { 'name': 'barney',  'age': 26 },
     *   { 'name': 'fred',    'age': 30 }
     * ];
     *
     * // using "_.pluck" callback shorthand
     * _.map(_.sortBy(characters, 'age'), _.values);
     * // => [['barney', 26], ['fred', 30], ['barney', 36], ['fred', 40]]
     *
     * // sorting by multiple properties
     * _.map(_.sortBy(characters, ['name', 'age']), _.values);
     * // = > [['barney', 26], ['barney', 36], ['fred', 30], ['fred', 40]]
     */
    function sortBy(collection, callback, thisArg) {
      var index = -1,
          isArr = isArray(callback),
          length = collection ? collection.length : 0,
          result = Array(typeof length == 'number' ? length : 0);

      if (!isArr) {
        callback = lodash.createCallback(callback, thisArg, 3);
      }
      forEach(collection, function(value, key, collection) {
        var object = result[++index] = getObject();
        if (isArr) {
          object.criteria = map(callback, function(key) { return value[key]; });
        } else {
          (object.criteria = getArray())[0] = callback(value, key, collection);
        }
        object.index = index;
        object.value = value;
      });

      length = result.length;
      result.sort(compareAscending);
      while (length--) {
        var object = result[length];
        result[length] = object.value;
        if (!isArr) {
          releaseArray(object.criteria);
        }
        releaseObject(object);
      }
      return result;
    }

    /**
     * Converts the `collection` to an array.
     *
     * @static
     * @memberOf _
     * @category Collections
     * @param {Array|Object|string} collection The collection to convert.
     * @returns {Array} Returns the new converted array.
     * @example
     *
     * (function() { return _.toArray(arguments).slice(1); })(1, 2, 3, 4);
     * // => [2, 3, 4]
     */
    function toArray(collection) {
      if (collection && typeof collection.length == 'number') {
        return (support.unindexedChars && isString(collection))
          ? collection.split('')
          : slice(collection);
      }
      return values(collection);
    }

    /**
     * Performs a deep comparison of each element in a `collection` to the given
     * `properties` object, returning an array of all elements that have equivalent
     * property values.
     *
     * @static
     * @memberOf _
     * @type Function
     * @category Collections
     * @param {Array|Object|string} collection The collection to iterate over.
     * @param {Object} props The object of property values to filter by.
     * @returns {Array} Returns a new array of elements that have the given properties.
     * @example
     *
     * var characters = [
     *   { 'name': 'barney', 'age': 36, 'pets': ['hoppy'] },
     *   { 'name': 'fred',   'age': 40, 'pets': ['baby puss', 'dino'] }
     * ];
     *
     * _.where(characters, { 'age': 36 });
     * // => [{ 'name': 'barney', 'age': 36, 'pets': ['hoppy'] }]
     *
     * _.where(characters, { 'pets': ['dino'] });
     * // => [{ 'name': 'fred', 'age': 40, 'pets': ['baby puss', 'dino'] }]
     */
    var where = filter;

    /*--------------------------------------------------------------------------*/

    /**
     * Creates an array with all falsey values removed. The values `false`, `null`,
     * `0`, `""`, `undefined`, and `NaN` are all falsey.
     *
     * @static
     * @memberOf _
     * @category Arrays
     * @param {Array} array The array to compact.
     * @returns {Array} Returns a new array of filtered values.
     * @example
     *
     * _.compact([0, 1, false, 2, '', 3]);
     * // => [1, 2, 3]
     */
    function compact(array) {
      var index = -1,
          length = array ? array.length : 0,
          result = [];

      while (++index < length) {
        var value = array[index];
        if (value) {
          result.push(value);
        }
      }
      return result;
    }

    /**
     * Creates an array excluding all values of the provided arrays using strict
     * equality for comparisons, i.e. `===`.
     *
     * @static
     * @memberOf _
     * @category Arrays
     * @param {Array} array The array to process.
     * @param {...Array} [values] The arrays of values to exclude.
     * @returns {Array} Returns a new array of filtered values.
     * @example
     *
     * _.difference([1, 2, 3, 4, 5], [5, 2, 10]);
     * // => [1, 3, 4]
     */
    function difference(array) {
      return baseDifference(array, baseFlatten(arguments, true, true, 1));
    }

    /**
     * This method is like `_.find` except that it returns the index of the first
     * element that passes the callback check, instead of the element itself.
     *
     * If a property name is provided for `callback` the created "_.pluck" style
     * callback will return the property value of the given element.
     *
     * If an object is provided for `callback` the created "_.where" style callback
     * will return `true` for elements that have the properties of the given object,
     * else `false`.
     *
     * @static
     * @memberOf _
     * @category Arrays
     * @param {Array} array The array to search.
     * @param {Function|Object|string} [callback=identity] The function called
     *  per iteration. If a property name or object is provided it will be used
     *  to create a "_.pluck" or "_.where" style callback, respectively.
     * @param {*} [thisArg] The `this` binding of `callback`.
     * @returns {number} Returns the index of the found element, else `-1`.
     * @example
     *
     * var characters = [
     *   { 'name': 'barney',  'age': 36, 'blocked': false },
     *   { 'name': 'fred',    'age': 40, 'blocked': true },
     *   { 'name': 'pebbles', 'age': 1,  'blocked': false }
     * ];
     *
     * _.findIndex(characters, function(chr) {
     *   return chr.age < 20;
     * });
     * // => 2
     *
     * // using "_.where" callback shorthand
     * _.findIndex(characters, { 'age': 36 });
     * // => 0
     *
     * // using "_.pluck" callback shorthand
     * _.findIndex(characters, 'blocked');
     * // => 1
     */
    function findIndex(array, callback, thisArg) {
      var index = -1,
          length = array ? array.length : 0;

      callback = lodash.createCallback(callback, thisArg, 3);
      while (++index < length) {
        if (callback(array[index], index, array)) {
          return index;
        }
      }
      return -1;
    }

    /**
     * This method is like `_.findIndex` except that it iterates over elements
     * of a `collection` from right to left.
     *
     * If a property name is provided for `callback` the created "_.pluck" style
     * callback will return the property value of the given element.
     *
     * If an object is provided for `callback` the created "_.where" style callback
     * will return `true` for elements that have the properties of the given object,
     * else `false`.
     *
     * @static
     * @memberOf _
     * @category Arrays
     * @param {Array} array The array to search.
     * @param {Function|Object|string} [callback=identity] The function called
     *  per iteration. If a property name or object is provided it will be used
     *  to create a "_.pluck" or "_.where" style callback, respectively.
     * @param {*} [thisArg] The `this` binding of `callback`.
     * @returns {number} Returns the index of the found element, else `-1`.
     * @example
     *
     * var characters = [
     *   { 'name': 'barney',  'age': 36, 'blocked': true },
     *   { 'name': 'fred',    'age': 40, 'blocked': false },
     *   { 'name': 'pebbles', 'age': 1,  'blocked': true }
     * ];
     *
     * _.findLastIndex(characters, function(chr) {
     *   return chr.age > 30;
     * });
     * // => 1
     *
     * // using "_.where" callback shorthand
     * _.findLastIndex(characters, { 'age': 36 });
     * // => 0
     *
     * // using "_.pluck" callback shorthand
     * _.findLastIndex(characters, 'blocked');
     * // => 2
     */
    function findLastIndex(array, callback, thisArg) {
      var length = array ? array.length : 0;
      callback = lodash.createCallback(callback, thisArg, 3);
      while (length--) {
        if (callback(array[length], length, array)) {
          return length;
        }
      }
      return -1;
    }

    /**
     * Gets the first element or first `n` elements of an array. If a callback
     * is provided elements at the beginning of the array are returned as long
     * as the callback returns truey. The callback is bound to `thisArg` and
     * invoked with three arguments; (value, index, array).
     *
     * If a property name is provided for `callback` the created "_.pluck" style
     * callback will return the property value of the given element.
     *
     * If an object is provided for `callback` the created "_.where" style callback
     * will return `true` for elements that have the properties of the given object,
     * else `false`.
     *
     * @static
     * @memberOf _
     * @alias head, take
     * @category Arrays
     * @param {Array} array The array to query.
     * @param {Function|Object|number|string} [callback] The function called
     *  per element or the number of elements to return. If a property name or
     *  object is provided it will be used to create a "_.pluck" or "_.where"
     *  style callback, respectively.
     * @param {*} [thisArg] The `this` binding of `callback`.
     * @returns {*} Returns the first element(s) of `array`.
     * @example
     *
     * _.first([1, 2, 3]);
     * // => 1
     *
     * _.first([1, 2, 3], 2);
     * // => [1, 2]
     *
     * _.first([1, 2, 3], function(num) {
     *   return num < 3;
     * });
     * // => [1, 2]
     *
     * var characters = [
     *   { 'name': 'barney',  'blocked': true,  'employer': 'slate' },
     *   { 'name': 'fred',    'blocked': false, 'employer': 'slate' },
     *   { 'name': 'pebbles', 'blocked': true,  'employer': 'na' }
     * ];
     *
     * // using "_.pluck" callback shorthand
     * _.first(characters, 'blocked');
     * // => [{ 'name': 'barney', 'blocked': true, 'employer': 'slate' }]
     *
     * // using "_.where" callback shorthand
     * _.pluck(_.first(characters, { 'employer': 'slate' }), 'name');
     * // => ['barney', 'fred']
     */
    function first(array, callback, thisArg) {
      var n = 0,
          length = array ? array.length : 0;

      if (typeof callback != 'number' && callback != null) {
        var index = -1;
        callback = lodash.createCallback(callback, thisArg, 3);
        while (++index < length && callback(array[index], index, array)) {
          n++;
        }
      } else {
        n = callback;
        if (n == null || thisArg) {
          return array ? array[0] : undefined;
        }
      }
      return slice(array, 0, nativeMin(nativeMax(0, n), length));
    }

    /**
     * Flattens a nested array (the nesting can be to any depth). If `isShallow`
     * is truey, the array will only be flattened a single level. If a callback
     * is provided each element of the array is passed through the callback before
     * flattening. The callback is bound to `thisArg` and invoked with three
     * arguments; (value, index, array).
     *
     * If a property name is provided for `callback` the created "_.pluck" style
     * callback will return the property value of the given element.
     *
     * If an object is provided for `callback` the created "_.where" style callback
     * will return `true` for elements that have the properties of the given object,
     * else `false`.
     *
     * @static
     * @memberOf _
     * @category Arrays
     * @param {Array} array The array to flatten.
     * @param {boolean} [isShallow=false] A flag to restrict flattening to a single level.
     * @param {Function|Object|string} [callback=identity] The function called
     *  per iteration. If a property name or object is provided it will be used
     *  to create a "_.pluck" or "_.where" style callback, respectively.
     * @param {*} [thisArg] The `this` binding of `callback`.
     * @returns {Array} Returns a new flattened array.
     * @example
     *
     * _.flatten([1, [2], [3, [[4]]]]);
     * // => [1, 2, 3, 4];
     *
     * _.flatten([1, [2], [3, [[4]]]], true);
     * // => [1, 2, 3, [[4]]];
     *
     * var characters = [
     *   { 'name': 'barney', 'age': 30, 'pets': ['hoppy'] },
     *   { 'name': 'fred',   'age': 40, 'pets': ['baby puss', 'dino'] }
     * ];
     *
     * // using "_.pluck" callback shorthand
     * _.flatten(characters, 'pets');
     * // => ['hoppy', 'baby puss', 'dino']
     */
    function flatten(array, isShallow, callback, thisArg) {
      // juggle arguments
      if (typeof isShallow != 'boolean' && isShallow != null) {
        thisArg = callback;
        callback = (typeof isShallow != 'function' && thisArg && thisArg[isShallow] === array) ? null : isShallow;
        isShallow = false;
      }
      if (callback != null) {
        array = map(array, callback, thisArg);
      }
      return baseFlatten(array, isShallow);
    }

    /**
     * Gets the index at which the first occurrence of `value` is found using
     * strict equality for comparisons, i.e. `===`. If the array is already sorted
     * providing `true` for `fromIndex` will run a faster binary search.
     *
     * @static
     * @memberOf _
     * @category Arrays
     * @param {Array} array The array to search.
     * @param {*} value The value to search for.
     * @param {boolean|number} [fromIndex=0] The index to search from or `true`
     *  to perform a binary search on a sorted array.
     * @returns {number} Returns the index of the matched value or `-1`.
     * @example
     *
     * _.indexOf([1, 2, 3, 1, 2, 3], 2);
     * // => 1
     *
     * _.indexOf([1, 2, 3, 1, 2, 3], 2, 3);
     * // => 4
     *
     * _.indexOf([1, 1, 2, 2, 3, 3], 2, true);
     * // => 2
     */
    function indexOf(array, value, fromIndex) {
      if (typeof fromIndex == 'number') {
        var length = array ? array.length : 0;
        fromIndex = (fromIndex < 0 ? nativeMax(0, length + fromIndex) : fromIndex || 0);
      } else if (fromIndex) {
        var index = sortedIndex(array, value);
        return array[index] === value ? index : -1;
      }
      return baseIndexOf(array, value, fromIndex);
    }

    /**
     * Gets all but the last element or last `n` elements of an array. If a
     * callback is provided elements at the end of the array are excluded from
     * the result as long as the callback returns truey. The callback is bound
     * to `thisArg` and invoked with three arguments; (value, index, array).
     *
     * If a property name is provided for `callback` the created "_.pluck" style
     * callback will return the property value of the given element.
     *
     * If an object is provided for `callback` the created "_.where" style callback
     * will return `true` for elements that have the properties of the given object,
     * else `false`.
     *
     * @static
     * @memberOf _
     * @category Arrays
     * @param {Array} array The array to query.
     * @param {Function|Object|number|string} [callback=1] The function called
     *  per element or the number of elements to exclude. If a property name or
     *  object is provided it will be used to create a "_.pluck" or "_.where"
     *  style callback, respectively.
     * @param {*} [thisArg] The `this` binding of `callback`.
     * @returns {Array} Returns a slice of `array`.
     * @example
     *
     * _.initial([1, 2, 3]);
     * // => [1, 2]
     *
     * _.initial([1, 2, 3], 2);
     * // => [1]
     *
     * _.initial([1, 2, 3], function(num) {
     *   return num > 1;
     * });
     * // => [1]
     *
     * var characters = [
     *   { 'name': 'barney',  'blocked': false, 'employer': 'slate' },
     *   { 'name': 'fred',    'blocked': true,  'employer': 'slate' },
     *   { 'name': 'pebbles', 'blocked': true,  'employer': 'na' }
     * ];
     *
     * // using "_.pluck" callback shorthand
     * _.initial(characters, 'blocked');
     * // => [{ 'name': 'barney',  'blocked': false, 'employer': 'slate' }]
     *
     * // using "_.where" callback shorthand
     * _.pluck(_.initial(characters, { 'employer': 'na' }), 'name');
     * // => ['barney', 'fred']
     */
    function initial(array, callback, thisArg) {
      var n = 0,
          length = array ? array.length : 0;

      if (typeof callback != 'number' && callback != null) {
        var index = length;
        callback = lodash.createCallback(callback, thisArg, 3);
        while (index-- && callback(array[index], index, array)) {
          n++;
        }
      } else {
        n = (callback == null || thisArg) ? 1 : callback || n;
      }
      return slice(array, 0, nativeMin(nativeMax(0, length - n), length));
    }

    /**
     * Creates an array of unique values present in all provided arrays using
     * strict equality for comparisons, i.e. `===`.
     *
     * @static
     * @memberOf _
     * @category Arrays
     * @param {...Array} [array] The arrays to inspect.
     * @returns {Array} Returns an array of shared values.
     * @example
     *
     * _.intersection([1, 2, 3], [5, 2, 1, 4], [2, 1]);
     * // => [1, 2]
     */
    function intersection() {
      var args = [],
          argsIndex = -1,
          argsLength = arguments.length,
          caches = getArray(),
          indexOf = getIndexOf(),
          trustIndexOf = indexOf === baseIndexOf,
          seen = getArray();

      while (++argsIndex < argsLength) {
        var value = arguments[argsIndex];
        if (isArray(value) || isArguments(value)) {
          args.push(value);
          caches.push(trustIndexOf && value.length >= largeArraySize &&
            createCache(argsIndex ? args[argsIndex] : seen));
        }
      }
      var array = args[0],
          index = -1,
          length = array ? array.length : 0,
          result = [];

      outer:
      while (++index < length) {
        var cache = caches[0];
        value = array[index];

        if ((cache ? cacheIndexOf(cache, value) : indexOf(seen, value)) < 0) {
          argsIndex = argsLength;
          (cache || seen).push(value);
          while (--argsIndex) {
            cache = caches[argsIndex];
            if ((cache ? cacheIndexOf(cache, value) : indexOf(args[argsIndex], value)) < 0) {
              continue outer;
            }
          }
          result.push(value);
        }
      }
      while (argsLength--) {
        cache = caches[argsLength];
        if (cache) {
          releaseObject(cache);
        }
      }
      releaseArray(caches);
      releaseArray(seen);
      return result;
    }

    /**
     * Gets the last element or last `n` elements of an array. If a callback is
     * provided elements at the end of the array are returned as long as the
     * callback returns truey. The callback is bound to `thisArg` and invoked
     * with three arguments; (value, index, array).
     *
     * If a property name is provided for `callback` the created "_.pluck" style
     * callback will return the property value of the given element.
     *
     * If an object is provided for `callback` the created "_.where" style callback
     * will return `true` for elements that have the properties of the given object,
     * else `false`.
     *
     * @static
     * @memberOf _
     * @category Arrays
     * @param {Array} array The array to query.
     * @param {Function|Object|number|string} [callback] The function called
     *  per element or the number of elements to return. If a property name or
     *  object is provided it will be used to create a "_.pluck" or "_.where"
     *  style callback, respectively.
     * @param {*} [thisArg] The `this` binding of `callback`.
     * @returns {*} Returns the last element(s) of `array`.
     * @example
     *
     * _.last([1, 2, 3]);
     * // => 3
     *
     * _.last([1, 2, 3], 2);
     * // => [2, 3]
     *
     * _.last([1, 2, 3], function(num) {
     *   return num > 1;
     * });
     * // => [2, 3]
     *
     * var characters = [
     *   { 'name': 'barney',  'blocked': false, 'employer': 'slate' },
     *   { 'name': 'fred',    'blocked': true,  'employer': 'slate' },
     *   { 'name': 'pebbles', 'blocked': true,  'employer': 'na' }
     * ];
     *
     * // using "_.pluck" callback shorthand
     * _.pluck(_.last(characters, 'blocked'), 'name');
     * // => ['fred', 'pebbles']
     *
     * // using "_.where" callback shorthand
     * _.last(characters, { 'employer': 'na' });
     * // => [{ 'name': 'pebbles', 'blocked': true, 'employer': 'na' }]
     */
    function last(array, callback, thisArg) {
      var n = 0,
          length = array ? array.length : 0;

      if (typeof callback != 'number' && callback != null) {
        var index = length;
        callback = lodash.createCallback(callback, thisArg, 3);
        while (index-- && callback(array[index], index, array)) {
          n++;
        }
      } else {
        n = callback;
        if (n == null || thisArg) {
          return array ? array[length - 1] : undefined;
        }
      }
      return slice(array, nativeMax(0, length - n));
    }

    /**
     * Gets the index at which the last occurrence of `value` is found using strict
     * equality for comparisons, i.e. `===`. If `fromIndex` is negative, it is used
     * as the offset from the end of the collection.
     *
     * If a property name is provided for `callback` the created "_.pluck" style
     * callback will return the property value of the given element.
     *
     * If an object is provided for `callback` the created "_.where" style callback
     * will return `true` for elements that have the properties of the given object,
     * else `false`.
     *
     * @static
     * @memberOf _
     * @category Arrays
     * @param {Array} array The array to search.
     * @param {*} value The value to search for.
     * @param {number} [fromIndex=array.length-1] The index to search from.
     * @returns {number} Returns the index of the matched value or `-1`.
     * @example
     *
     * _.lastIndexOf([1, 2, 3, 1, 2, 3], 2);
     * // => 4
     *
     * _.lastIndexOf([1, 2, 3, 1, 2, 3], 2, 3);
     * // => 1
     */
    function lastIndexOf(array, value, fromIndex) {
      var index = array ? array.length : 0;
      if (typeof fromIndex == 'number') {
        index = (fromIndex < 0 ? nativeMax(0, index + fromIndex) : nativeMin(fromIndex, index - 1)) + 1;
      }
      while (index--) {
        if (array[index] === value) {
          return index;
        }
      }
      return -1;
    }

    /**
     * Removes all provided values from the given array using strict equality for
     * comparisons, i.e. `===`.
     *
     * @static
     * @memberOf _
     * @category Arrays
     * @param {Array} array The array to modify.
     * @param {...*} [value] The values to remove.
     * @returns {Array} Returns `array`.
     * @example
     *
     * var array = [1, 2, 3, 1, 2, 3];
     * _.pull(array, 2, 3);
     * console.log(array);
     * // => [1, 1]
     */
    function pull(array) {
      var args = arguments,
          argsIndex = 0,
          argsLength = args.length,
          length = array ? array.length : 0;

      while (++argsIndex < argsLength) {
        var index = -1,
            value = args[argsIndex];
        while (++index < length) {
          if (array[index] === value) {
            splice.call(array, index--, 1);
            length--;
          }
        }
      }
      return array;
    }

    /**
     * Creates an array of numbers (positive and/or negative) progressing from
     * `start` up to but not including `end`. If `start` is less than `stop` a
     * zero-length range is created unless a negative `step` is specified.
     *
     * @static
     * @memberOf _
     * @category Arrays
     * @param {number} [start=0] The start of the range.
     * @param {number} end The end of the range.
     * @param {number} [step=1] The value to increment or decrement by.
     * @returns {Array} Returns a new range array.
     * @example
     *
     * _.range(4);
     * // => [0, 1, 2, 3]
     *
     * _.range(1, 5);
     * // => [1, 2, 3, 4]
     *
     * _.range(0, 20, 5);
     * // => [0, 5, 10, 15]
     *
     * _.range(0, -4, -1);
     * // => [0, -1, -2, -3]
     *
     * _.range(1, 4, 0);
     * // => [1, 1, 1]
     *
     * _.range(0);
     * // => []
     */
    function range(start, end, step) {
      start = +start || 0;
      step = typeof step == 'number' ? step : (+step || 1);

      if (end == null) {
        end = start;
        start = 0;
      }
      // use `Array(length)` so engines like Chakra and V8 avoid slower modes
      // http://youtu.be/XAqIpGU8ZZk#t=17m25s
      var index = -1,
          length = nativeMax(0, ceil((end - start) / (step || 1))),
          result = Array(length);

      while (++index < length) {
        result[index] = start;
        start += step;
      }
      return result;
    }

    /**
     * Removes all elements from an array that the callback returns truey for
     * and returns an array of removed elements. The callback is bound to `thisArg`
     * and invoked with three arguments; (value, index, array).
     *
     * If a property name is provided for `callback` the created "_.pluck" style
     * callback will return the property value of the given element.
     *
     * If an object is provided for `callback` the created "_.where" style callback
     * will return `true` for elements that have the properties of the given object,
     * else `false`.
     *
     * @static
     * @memberOf _
     * @category Arrays
     * @param {Array} array The array to modify.
     * @param {Function|Object|string} [callback=identity] The function called
     *  per iteration. If a property name or object is provided it will be used
     *  to create a "_.pluck" or "_.where" style callback, respectively.
     * @param {*} [thisArg] The `this` binding of `callback`.
     * @returns {Array} Returns a new array of removed elements.
     * @example
     *
     * var array = [1, 2, 3, 4, 5, 6];
     * var evens = _.remove(array, function(num) { return num % 2 == 0; });
     *
     * console.log(array);
     * // => [1, 3, 5]
     *
     * console.log(evens);
     * // => [2, 4, 6]
     */
    function remove(array, callback, thisArg) {
      var index = -1,
          length = array ? array.length : 0,
          result = [];

      callback = lodash.createCallback(callback, thisArg, 3);
      while (++index < length) {
        var value = array[index];
        if (callback(value, index, array)) {
          result.push(value);
          splice.call(array, index--, 1);
          length--;
        }
      }
      return result;
    }

    /**
     * The opposite of `_.initial` this method gets all but the first element or
     * first `n` elements of an array. If a callback function is provided elements
     * at the beginning of the array are excluded from the result as long as the
     * callback returns truey. The callback is bound to `thisArg` and invoked
     * with three arguments; (value, index, array).
     *
     * If a property name is provided for `callback` the created "_.pluck" style
     * callback will return the property value of the given element.
     *
     * If an object is provided for `callback` the created "_.where" style callback
     * will return `true` for elements that have the properties of the given object,
     * else `false`.
     *
     * @static
     * @memberOf _
     * @alias drop, tail
     * @category Arrays
     * @param {Array} array The array to query.
     * @param {Function|Object|number|string} [callback=1] The function called
     *  per element or the number of elements to exclude. If a property name or
     *  object is provided it will be used to create a "_.pluck" or "_.where"
     *  style callback, respectively.
     * @param {*} [thisArg] The `this` binding of `callback`.
     * @returns {Array} Returns a slice of `array`.
     * @example
     *
     * _.rest([1, 2, 3]);
     * // => [2, 3]
     *
     * _.rest([1, 2, 3], 2);
     * // => [3]
     *
     * _.rest([1, 2, 3], function(num) {
     *   return num < 3;
     * });
     * // => [3]
     *
     * var characters = [
     *   { 'name': 'barney',  'blocked': true,  'employer': 'slate' },
     *   { 'name': 'fred',    'blocked': false,  'employer': 'slate' },
     *   { 'name': 'pebbles', 'blocked': true, 'employer': 'na' }
     * ];
     *
     * // using "_.pluck" callback shorthand
     * _.pluck(_.rest(characters, 'blocked'), 'name');
     * // => ['fred', 'pebbles']
     *
     * // using "_.where" callback shorthand
     * _.rest(characters, { 'employer': 'slate' });
     * // => [{ 'name': 'pebbles', 'blocked': true, 'employer': 'na' }]
     */
    function rest(array, callback, thisArg) {
      if (typeof callback != 'number' && callback != null) {
        var n = 0,
            index = -1,
            length = array ? array.length : 0;

        callback = lodash.createCallback(callback, thisArg, 3);
        while (++index < length && callback(array[index], index, array)) {
          n++;
        }
      } else {
        n = (callback == null || thisArg) ? 1 : nativeMax(0, callback);
      }
      return slice(array, n);
    }

    /**
     * Uses a binary search to determine the smallest index at which a value
     * should be inserted into a given sorted array in order to maintain the sort
     * order of the array. If a callback is provided it will be executed for
     * `value` and each element of `array` to compute their sort ranking. The
     * callback is bound to `thisArg` and invoked with one argument; (value).
     *
     * If a property name is provided for `callback` the created "_.pluck" style
     * callback will return the property value of the given element.
     *
     * If an object is provided for `callback` the created "_.where" style callback
     * will return `true` for elements that have the properties of the given object,
     * else `false`.
     *
     * @static
     * @memberOf _
     * @category Arrays
     * @param {Array} array The array to inspect.
     * @param {*} value The value to evaluate.
     * @param {Function|Object|string} [callback=identity] The function called
     *  per iteration. If a property name or object is provided it will be used
     *  to create a "_.pluck" or "_.where" style callback, respectively.
     * @param {*} [thisArg] The `this` binding of `callback`.
     * @returns {number} Returns the index at which `value` should be inserted
     *  into `array`.
     * @example
     *
     * _.sortedIndex([20, 30, 50], 40);
     * // => 2
     *
     * // using "_.pluck" callback shorthand
     * _.sortedIndex([{ 'x': 20 }, { 'x': 30 }, { 'x': 50 }], { 'x': 40 }, 'x');
     * // => 2
     *
     * var dict = {
     *   'wordToNumber': { 'twenty': 20, 'thirty': 30, 'fourty': 40, 'fifty': 50 }
     * };
     *
     * _.sortedIndex(['twenty', 'thirty', 'fifty'], 'fourty', function(word) {
     *   return dict.wordToNumber[word];
     * });
     * // => 2
     *
     * _.sortedIndex(['twenty', 'thirty', 'fifty'], 'fourty', function(word) {
     *   return this.wordToNumber[word];
     * }, dict);
     * // => 2
     */
    function sortedIndex(array, value, callback, thisArg) {
      var low = 0,
          high = array ? array.length : low;

      // explicitly reference `identity` for better inlining in Firefox
      callback = callback ? lodash.createCallback(callback, thisArg, 1) : identity;
      value = callback(value);

      while (low < high) {
        var mid = (low + high) >>> 1;
        (callback(array[mid]) < value)
          ? low = mid + 1
          : high = mid;
      }
      return low;
    }

    /**
     * Creates an array of unique values, in order, of the provided arrays using
     * strict equality for comparisons, i.e. `===`.
     *
     * @static
     * @memberOf _
     * @category Arrays
     * @param {...Array} [array] The arrays to inspect.
     * @returns {Array} Returns an array of combined values.
     * @example
     *
     * _.union([1, 2, 3], [5, 2, 1, 4], [2, 1]);
     * // => [1, 2, 3, 5, 4]
     */
    function union() {
      return baseUniq(baseFlatten(arguments, true, true));
    }

    /**
     * Creates a duplicate-value-free version of an array using strict equality
     * for comparisons, i.e. `===`. If the array is sorted, providing
     * `true` for `isSorted` will use a faster algorithm. If a callback is provided
     * each element of `array` is passed through the callback before uniqueness
     * is computed. The callback is bound to `thisArg` and invoked with three
     * arguments; (value, index, array).
     *
     * If a property name is provided for `callback` the created "_.pluck" style
     * callback will return the property value of the given element.
     *
     * If an object is provided for `callback` the created "_.where" style callback
     * will return `true` for elements that have the properties of the given object,
     * else `false`.
     *
     * @static
     * @memberOf _
     * @alias unique
     * @category Arrays
     * @param {Array} array The array to process.
     * @param {boolean} [isSorted=false] A flag to indicate that `array` is sorted.
     * @param {Function|Object|string} [callback=identity] The function called
     *  per iteration. If a property name or object is provided it will be used
     *  to create a "_.pluck" or "_.where" style callback, respectively.
     * @param {*} [thisArg] The `this` binding of `callback`.
     * @returns {Array} Returns a duplicate-value-free array.
     * @example
     *
     * _.uniq([1, 2, 1, 3, 1]);
     * // => [1, 2, 3]
     *
     * _.uniq([1, 1, 2, 2, 3], true);
     * // => [1, 2, 3]
     *
     * _.uniq(['A', 'b', 'C', 'a', 'B', 'c'], function(letter) { return letter.toLowerCase(); });
     * // => ['A', 'b', 'C']
     *
     * _.uniq([1, 2.5, 3, 1.5, 2, 3.5], function(num) { return this.floor(num); }, Math);
     * // => [1, 2.5, 3]
     *
     * // using "_.pluck" callback shorthand
     * _.uniq([{ 'x': 1 }, { 'x': 2 }, { 'x': 1 }], 'x');
     * // => [{ 'x': 1 }, { 'x': 2 }]
     */
    function uniq(array, isSorted, callback, thisArg) {
      // juggle arguments
      if (typeof isSorted != 'boolean' && isSorted != null) {
        thisArg = callback;
        callback = (typeof isSorted != 'function' && thisArg && thisArg[isSorted] === array) ? null : isSorted;
        isSorted = false;
      }
      if (callback != null) {
        callback = lodash.createCallback(callback, thisArg, 3);
      }
      return baseUniq(array, isSorted, callback);
    }

    /**
     * Creates an array excluding all provided values using strict equality for
     * comparisons, i.e. `===`.
     *
     * @static
     * @memberOf _
     * @category Arrays
     * @param {Array} array The array to filter.
     * @param {...*} [value] The values to exclude.
     * @returns {Array} Returns a new array of filtered values.
     * @example
     *
     * _.without([1, 2, 1, 0, 3, 1, 4], 0, 1);
     * // => [2, 3, 4]
     */
    function without(array) {
      return baseDifference(array, slice(arguments, 1));
    }

    /**
     * Creates an array that is the symmetric difference of the provided arrays.
     * See http://en.wikipedia.org/wiki/Symmetric_difference.
     *
     * @static
     * @memberOf _
     * @category Arrays
     * @param {...Array} [array] The arrays to inspect.
     * @returns {Array} Returns an array of values.
     * @example
     *
     * _.xor([1, 2, 3], [5, 2, 1, 4]);
     * // => [3, 5, 4]
     *
     * _.xor([1, 2, 5], [2, 3, 5], [3, 4, 5]);
     * // => [1, 4, 5]
     */
    function xor() {
      var index = -1,
          length = arguments.length;

      while (++index < length) {
        var array = arguments[index];
        if (isArray(array) || isArguments(array)) {
          var result = result
            ? baseUniq(baseDifference(result, array).concat(baseDifference(array, result)))
            : array;
        }
      }
      return result || [];
    }

    /**
     * Creates an array of grouped elements, the first of which contains the first
     * elements of the given arrays, the second of which contains the second
     * elements of the given arrays, and so on.
     *
     * @static
     * @memberOf _
     * @alias unzip
     * @category Arrays
     * @param {...Array} [array] Arrays to process.
     * @returns {Array} Returns a new array of grouped elements.
     * @example
     *
     * _.zip(['fred', 'barney'], [30, 40], [true, false]);
     * // => [['fred', 30, true], ['barney', 40, false]]
     */
    function zip() {
      var array = arguments.length > 1 ? arguments : arguments[0],
          index = -1,
          length = array ? max(pluck(array, 'length')) : 0,
          result = Array(length < 0 ? 0 : length);

      while (++index < length) {
        result[index] = pluck(array, index);
      }
      return result;
    }

    /**
     * Creates an object composed from arrays of `keys` and `values`. Provide
     * either a single two dimensional array, i.e. `[[key1, value1], [key2, value2]]`
     * or two arrays, one of `keys` and one of corresponding `values`.
     *
     * @static
     * @memberOf _
     * @alias object
     * @category Arrays
     * @param {Array} keys The array of keys.
     * @param {Array} [values=[]] The array of values.
     * @returns {Object} Returns an object composed of the given keys and
     *  corresponding values.
     * @example
     *
     * _.zipObject(['fred', 'barney'], [30, 40]);
     * // => { 'fred': 30, 'barney': 40 }
     */
    function zipObject(keys, values) {
      var index = -1,
          length = keys ? keys.length : 0,
          result = {};

      if (!values && length && !isArray(keys[0])) {
        values = [];
      }
      while (++index < length) {
        var key = keys[index];
        if (values) {
          result[key] = values[index];
        } else if (key) {
          result[key[0]] = key[1];
        }
      }
      return result;
    }

    /*--------------------------------------------------------------------------*/

    /**
     * Creates a function that executes `func`, with  the `this` binding and
     * arguments of the created function, only after being called `n` times.
     *
     * @static
     * @memberOf _
     * @category Functions
     * @param {number} n The number of times the function must be called before
     *  `func` is executed.
     * @param {Function} func The function to restrict.
     * @returns {Function} Returns the new restricted function.
     * @example
     *
     * var saves = ['profile', 'settings'];
     *
     * var done = _.after(saves.length, function() {
     *   console.log('Done saving!');
     * });
     *
     * _.forEach(saves, function(type) {
     *   asyncSave({ 'type': type, 'complete': done });
     * });
     * // => logs 'Done saving!', after all saves have completed
     */
    function after(n, func) {
      if (!isFunction(func)) {
        throw new TypeError;
      }
      return function() {
        if (--n < 1) {
          return func.apply(this, arguments);
        }
      };
    }

    /**
     * Creates a function that, when called, invokes `func` with the `this`
     * binding of `thisArg` and prepends any additional `bind` arguments to those
     * provided to the bound function.
     *
     * @static
     * @memberOf _
     * @category Functions
     * @param {Function} func The function to bind.
     * @param {*} [thisArg] The `this` binding of `func`.
     * @param {...*} [arg] Arguments to be partially applied.
     * @returns {Function} Returns the new bound function.
     * @example
     *
     * var func = function(greeting) {
     *   return greeting + ' ' + this.name;
     * };
     *
     * func = _.bind(func, { 'name': 'fred' }, 'hi');
     * func();
     * // => 'hi fred'
     */
    function bind(func, thisArg) {
      return arguments.length > 2
        ? createWrapper(func, 17, slice(arguments, 2), null, thisArg)
        : createWrapper(func, 1, null, null, thisArg);
    }

    /**
     * Binds methods of an object to the object itself, overwriting the existing
     * method. Method names may be specified as individual arguments or as arrays
     * of method names. If no method names are provided all the function properties
     * of `object` will be bound.
     *
     * @static
     * @memberOf _
     * @category Functions
     * @param {Object} object The object to bind and assign the bound methods to.
     * @param {...string} [methodName] The object method names to
     *  bind, specified as individual method names or arrays of method names.
     * @returns {Object} Returns `object`.
     * @example
     *
     * var view = {
     *   'label': 'docs',
     *   'onClick': function() { console.log('clicked ' + this.label); }
     * };
     *
     * _.bindAll(view);
     * jQuery('#docs').on('click', view.onClick);
     * // => logs 'clicked docs', when the button is clicked
     */
    function bindAll(object) {
      var funcs = arguments.length > 1 ? baseFlatten(arguments, true, false, 1) : functions(object),
          index = -1,
          length = funcs.length;

      while (++index < length) {
        var key = funcs[index];
        object[key] = createWrapper(object[key], 1, null, null, object);
      }
      return object;
    }

    /**
     * Creates a function that, when called, invokes the method at `object[key]`
     * and prepends any additional `bindKey` arguments to those provided to the bound
     * function. This method differs from `_.bind` by allowing bound functions to
     * reference methods that will be redefined or don't yet exist.
     * See http://michaux.ca/articles/lazy-function-definition-pattern.
     *
     * @static
     * @memberOf _
     * @category Functions
     * @param {Object} object The object the method belongs to.
     * @param {string} key The key of the method.
     * @param {...*} [arg] Arguments to be partially applied.
     * @returns {Function} Returns the new bound function.
     * @example
     *
     * var object = {
     *   'name': 'fred',
     *   'greet': function(greeting) {
     *     return greeting + ' ' + this.name;
     *   }
     * };
     *
     * var func = _.bindKey(object, 'greet', 'hi');
     * func();
     * // => 'hi fred'
     *
     * object.greet = function(greeting) {
     *   return greeting + 'ya ' + this.name + '!';
     * };
     *
     * func();
     * // => 'hiya fred!'
     */
    function bindKey(object, key) {
      return arguments.length > 2
        ? createWrapper(key, 19, slice(arguments, 2), null, object)
        : createWrapper(key, 3, null, null, object);
    }

    /**
     * Creates a function that is the composition of the provided functions,
     * where each function consumes the return value of the function that follows.
     * For example, composing the functions `f()`, `g()`, and `h()` produces `f(g(h()))`.
     * Each function is executed with the `this` binding of the composed function.
     *
     * @static
     * @memberOf _
     * @category Functions
     * @param {...Function} [func] Functions to compose.
     * @returns {Function} Returns the new composed function.
     * @example
     *
     * var realNameMap = {
     *   'pebbles': 'penelope'
     * };
     *
     * var format = function(name) {
     *   name = realNameMap[name.toLowerCase()] || name;
     *   return name.charAt(0).toUpperCase() + name.slice(1).toLowerCase();
     * };
     *
     * var greet = function(formatted) {
     *   return 'Hiya ' + formatted + '!';
     * };
     *
     * var welcome = _.compose(greet, format);
     * welcome('pebbles');
     * // => 'Hiya Penelope!'
     */
    function compose() {
      var funcs = arguments,
          length = funcs.length;

      while (length--) {
        if (!isFunction(funcs[length])) {
          throw new TypeError;
        }
      }
      return function() {
        var args = arguments,
            length = funcs.length;

        while (length--) {
          args = [funcs[length].apply(this, args)];
        }
        return args[0];
      };
    }

    /**
     * Creates a function which accepts one or more arguments of `func` that when
     * invoked either executes `func` returning its result, if all `func` arguments
     * have been provided, or returns a function that accepts one or more of the
     * remaining `func` arguments, and so on. The arity of `func` can be specified
     * if `func.length` is not sufficient.
     *
     * @static
     * @memberOf _
     * @category Functions
     * @param {Function} func The function to curry.
     * @param {number} [arity=func.length] The arity of `func`.
     * @returns {Function} Returns the new curried function.
     * @example
     *
     * var curried = _.curry(function(a, b, c) {
     *   console.log(a + b + c);
     * });
     *
     * curried(1)(2)(3);
     * // => 6
     *
     * curried(1, 2)(3);
     * // => 6
     *
     * curried(1, 2, 3);
     * // => 6
     */
    function curry(func, arity) {
      arity = typeof arity == 'number' ? arity : (+arity || func.length);
      return createWrapper(func, 4, null, null, null, arity);
    }

    /**
     * Creates a function that will delay the execution of `func` until after
     * `wait` milliseconds have elapsed since the last time it was invoked.
     * Provide an options object to indicate that `func` should be invoked on
     * the leading and/or trailing edge of the `wait` timeout. Subsequent calls
     * to the debounced function will return the result of the last `func` call.
     *
     * Note: If `leading` and `trailing` options are `true` `func` will be called
     * on the trailing edge of the timeout only if the the debounced function is
     * invoked more than once during the `wait` timeout.
     *
     * @static
     * @memberOf _
     * @category Functions
     * @param {Function} func The function to debounce.
     * @param {number} wait The number of milliseconds to delay.
     * @param {Object} [options] The options object.
     * @param {boolean} [options.leading=false] Specify execution on the leading edge of the timeout.
     * @param {number} [options.maxWait] The maximum time `func` is allowed to be delayed before it's called.
     * @param {boolean} [options.trailing=true] Specify execution on the trailing edge of the timeout.
     * @returns {Function} Returns the new debounced function.
     * @example
     *
     * // avoid costly calculations while the window size is in flux
     * var lazyLayout = _.debounce(calculateLayout, 150);
     * jQuery(window).on('resize', lazyLayout);
     *
     * // execute `sendMail` when the click event is fired, debouncing subsequent calls
     * jQuery('#postbox').on('click', _.debounce(sendMail, 300, {
     *   'leading': true,
     *   'trailing': false
     * });
     *
     * // ensure `batchLog` is executed once after 1 second of debounced calls
     * var source = new EventSource('/stream');
     * source.addEventListener('message', _.debounce(batchLog, 250, {
     *   'maxWait': 1000
     * }, false);
     */
    function debounce(func, wait, options) {
      var args,
          maxTimeoutId,
          result,
          stamp,
          thisArg,
          timeoutId,
          trailingCall,
          lastCalled = 0,
          maxWait = false,
          trailing = true;

      if (!isFunction(func)) {
        throw new TypeError;
      }
      wait = nativeMax(0, wait) || 0;
      if (options === true) {
        var leading = true;
        trailing = false;
      } else if (isObject(options)) {
        leading = options.leading;
        maxWait = 'maxWait' in options && (nativeMax(wait, options.maxWait) || 0);
        trailing = 'trailing' in options ? options.trailing : trailing;
      }
      var delayed = function() {
        var remaining = wait - (now() - stamp);
        if (remaining <= 0) {
          if (maxTimeoutId) {
            clearTimeout(maxTimeoutId);
          }
          var isCalled = trailingCall;
          maxTimeoutId = timeoutId = trailingCall = undefined;
          if (isCalled) {
            lastCalled = now();
            result = func.apply(thisArg, args);
            if (!timeoutId && !maxTimeoutId) {
              args = thisArg = null;
            }
          }
        } else {
          timeoutId = setTimeout(delayed, remaining);
        }
      };

      var maxDelayed = function() {
        if (timeoutId) {
          clearTimeout(timeoutId);
        }
        maxTimeoutId = timeoutId = trailingCall = undefined;
        if (trailing || (maxWait !== wait)) {
          lastCalled = now();
          result = func.apply(thisArg, args);
          if (!timeoutId && !maxTimeoutId) {
            args = thisArg = null;
          }
        }
      };

      return function() {
        args = arguments;
        stamp = now();
        thisArg = this;
        trailingCall = trailing && (timeoutId || !leading);

        if (maxWait === false) {
          var leadingCall = leading && !timeoutId;
        } else {
          if (!maxTimeoutId && !leading) {
            lastCalled = stamp;
          }
          var remaining = maxWait - (stamp - lastCalled),
              isCalled = remaining <= 0;

          if (isCalled) {
            if (maxTimeoutId) {
              maxTimeoutId = clearTimeout(maxTimeoutId);
            }
            lastCalled = stamp;
            result = func.apply(thisArg, args);
          }
          else if (!maxTimeoutId) {
            maxTimeoutId = setTimeout(maxDelayed, remaining);
          }
        }
        if (isCalled && timeoutId) {
          timeoutId = clearTimeout(timeoutId);
        }
        else if (!timeoutId && wait !== maxWait) {
          timeoutId = setTimeout(delayed, wait);
        }
        if (leadingCall) {
          isCalled = true;
          result = func.apply(thisArg, args);
        }
        if (isCalled && !timeoutId && !maxTimeoutId) {
          args = thisArg = null;
        }
        return result;
      };
    }

    /**
     * Defers executing the `func` function until the current call stack has cleared.
     * Additional arguments will be provided to `func` when it is invoked.
     *
     * @static
     * @memberOf _
     * @category Functions
     * @param {Function} func The function to defer.
     * @param {...*} [arg] Arguments to invoke the function with.
     * @returns {number} Returns the timer id.
     * @example
     *
     * _.defer(function(text) { console.log(text); }, 'deferred');
     * // logs 'deferred' after one or more milliseconds
     */
    function defer(func) {
      if (!isFunction(func)) {
        throw new TypeError;
      }
      var args = slice(arguments, 1);
      return setTimeout(function() { func.apply(undefined, args); }, 1);
    }

    /**
     * Executes the `func` function after `wait` milliseconds. Additional arguments
     * will be provided to `func` when it is invoked.
     *
     * @static
     * @memberOf _
     * @category Functions
     * @param {Function} func The function to delay.
     * @param {number} wait The number of milliseconds to delay execution.
     * @param {...*} [arg] Arguments to invoke the function with.
     * @returns {number} Returns the timer id.
     * @example
     *
     * _.delay(function(text) { console.log(text); }, 1000, 'later');
     * // => logs 'later' after one second
     */
    function delay(func, wait) {
      if (!isFunction(func)) {
        throw new TypeError;
      }
      var args = slice(arguments, 2);
      return setTimeout(function() { func.apply(undefined, args); }, wait);
    }

    /**
     * Creates a function that memoizes the result of `func`. If `resolver` is
     * provided it will be used to determine the cache key for storing the result
     * based on the arguments provided to the memoized function. By default, the
     * first argument provided to the memoized function is used as the cache key.
     * The `func` is executed with the `this` binding of the memoized function.
     * The result cache is exposed as the `cache` property on the memoized function.
     *
     * @static
     * @memberOf _
     * @category Functions
     * @param {Function} func The function to have its output memoized.
     * @param {Function} [resolver] A function used to resolve the cache key.
     * @returns {Function} Returns the new memoizing function.
     * @example
     *
     * var fibonacci = _.memoize(function(n) {
     *   return n < 2 ? n : fibonacci(n - 1) + fibonacci(n - 2);
     * });
     *
     * fibonacci(9)
     * // => 34
     *
     * var data = {
     *   'fred': { 'name': 'fred', 'age': 40 },
     *   'pebbles': { 'name': 'pebbles', 'age': 1 }
     * };
     *
     * // modifying the result cache
     * var get = _.memoize(function(name) { return data[name]; }, _.identity);
     * get('pebbles');
     * // => { 'name': 'pebbles', 'age': 1 }
     *
     * get.cache.pebbles.name = 'penelope';
     * get('pebbles');
     * // => { 'name': 'penelope', 'age': 1 }
     */
    function memoize(func, resolver) {
      if (!isFunction(func)) {
        throw new TypeError;
      }
      var memoized = function() {
        var cache = memoized.cache,
            key = resolver ? resolver.apply(this, arguments) : keyPrefix + arguments[0];

        return hasOwnProperty.call(cache, key)
          ? cache[key]
          : (cache[key] = func.apply(this, arguments));
      }
      memoized.cache = {};
      return memoized;
    }

    /**
     * Creates a function that is restricted to execute `func` once. Repeat calls to
     * the function will return the value of the first call. The `func` is executed
     * with the `this` binding of the created function.
     *
     * @static
     * @memberOf _
     * @category Functions
     * @param {Function} func The function to restrict.
     * @returns {Function} Returns the new restricted function.
     * @example
     *
     * var initialize = _.once(createApplication);
     * initialize();
     * initialize();
     * // `initialize` executes `createApplication` once
     */
    function once(func) {
      var ran,
          result;

      if (!isFunction(func)) {
        throw new TypeError;
      }
      return function() {
        if (ran) {
          return result;
        }
        ran = true;
        result = func.apply(this, arguments);

        // clear the `func` variable so the function may be garbage collected
        func = null;
        return result;
      };
    }

    /**
     * Creates a function that, when called, invokes `func` with any additional
     * `partial` arguments prepended to those provided to the new function. This
     * method is similar to `_.bind` except it does **not** alter the `this` binding.
     *
     * @static
     * @memberOf _
     * @category Functions
     * @param {Function} func The function to partially apply arguments to.
     * @param {...*} [arg] Arguments to be partially applied.
     * @returns {Function} Returns the new partially applied function.
     * @example
     *
     * var greet = function(greeting, name) { return greeting + ' ' + name; };
     * var hi = _.partial(greet, 'hi');
     * hi('fred');
     * // => 'hi fred'
     */
    function partial(func) {
      return createWrapper(func, 16, slice(arguments, 1));
    }

    /**
     * This method is like `_.partial` except that `partial` arguments are
     * appended to those provided to the new function.
     *
     * @static
     * @memberOf _
     * @category Functions
     * @param {Function} func The function to partially apply arguments to.
     * @param {...*} [arg] Arguments to be partially applied.
     * @returns {Function} Returns the new partially applied function.
     * @example
     *
     * var defaultsDeep = _.partialRight(_.merge, _.defaults);
     *
     * var options = {
     *   'variable': 'data',
     *   'imports': { 'jq': $ }
     * };
     *
     * defaultsDeep(options, _.templateSettings);
     *
     * options.variable
     * // => 'data'
     *
     * options.imports
     * // => { '_': _, 'jq': $ }
     */
    function partialRight(func) {
      return createWrapper(func, 32, null, slice(arguments, 1));
    }

    /**
     * Creates a function that, when executed, will only call the `func` function
     * at most once per every `wait` milliseconds. Provide an options object to
     * indicate that `func` should be invoked on the leading and/or trailing edge
     * of the `wait` timeout. Subsequent calls to the throttled function will
     * return the result of the last `func` call.
     *
     * Note: If `leading` and `trailing` options are `true` `func` will be called
     * on the trailing edge of the timeout only if the the throttled function is
     * invoked more than once during the `wait` timeout.
     *
     * @static
     * @memberOf _
     * @category Functions
     * @param {Function} func The function to throttle.
     * @param {number} wait The number of milliseconds to throttle executions to.
     * @param {Object} [options] The options object.
     * @param {boolean} [options.leading=true] Specify execution on the leading edge of the timeout.
     * @param {boolean} [options.trailing=true] Specify execution on the trailing edge of the timeout.
     * @returns {Function} Returns the new throttled function.
     * @example
     *
     * // avoid excessively updating the position while scrolling
     * var throttled = _.throttle(updatePosition, 100);
     * jQuery(window).on('scroll', throttled);
     *
     * // execute `renewToken` when the click event is fired, but not more than once every 5 minutes
     * jQuery('.interactive').on('click', _.throttle(renewToken, 300000, {
     *   'trailing': false
     * }));
     */
    function throttle(func, wait, options) {
      var leading = true,
          trailing = true;

      if (!isFunction(func)) {
        throw new TypeError;
      }
      if (options === false) {
        leading = false;
      } else if (isObject(options)) {
        leading = 'leading' in options ? options.leading : leading;
        trailing = 'trailing' in options ? options.trailing : trailing;
      }
      debounceOptions.leading = leading;
      debounceOptions.maxWait = wait;
      debounceOptions.trailing = trailing;

      return debounce(func, wait, debounceOptions);
    }

    /**
     * Creates a function that provides `value` to the wrapper function as its
     * first argument. Additional arguments provided to the function are appended
     * to those provided to the wrapper function. The wrapper is executed with
     * the `this` binding of the created function.
     *
     * @static
     * @memberOf _
     * @category Functions
     * @param {*} value The value to wrap.
     * @param {Function} wrapper The wrapper function.
     * @returns {Function} Returns the new function.
     * @example
     *
     * var p = _.wrap(_.escape, function(func, text) {
     *   return '<p>' + func(text) + '</p>';
     * });
     *
     * p('Fred, Wilma, & Pebbles');
     * // => '<p>Fred, Wilma, &amp; Pebbles</p>'
     */
    function wrap(value, wrapper) {
      return createWrapper(wrapper, 16, [value]);
    }

    /*--------------------------------------------------------------------------*/

    /**
     * Creates a function that returns `value`.
     *
     * @static
     * @memberOf _
     * @category Utilities
     * @param {*} value The value to return from the new function.
     * @returns {Function} Returns the new function.
     * @example
     *
     * var object = { 'name': 'fred' };
     * var getter = _.constant(object);
     * getter() === object;
     * // => true
     */
    function constant(value) {
      return function() {
        return value;
      };
    }

    /**
     * Produces a callback bound to an optional `thisArg`. If `func` is a property
     * name the created callback will return the property value for a given element.
     * If `func` is an object the created callback will return `true` for elements
     * that contain the equivalent object properties, otherwise it will return `false`.
     *
     * @static
     * @memberOf _
     * @category Utilities
     * @param {*} [func=identity] The value to convert to a callback.
     * @param {*} [thisArg] The `this` binding of the created callback.
     * @param {number} [argCount] The number of arguments the callback accepts.
     * @returns {Function} Returns a callback function.
     * @example
     *
     * var characters = [
     *   { 'name': 'barney', 'age': 36 },
     *   { 'name': 'fred',   'age': 40 }
     * ];
     *
     * // wrap to create custom callback shorthands
     * _.createCallback = _.wrap(_.createCallback, function(func, callback, thisArg) {
     *   var match = /^(.+?)__([gl]t)(.+)$/.exec(callback);
     *   return !match ? func(callback, thisArg) : function(object) {
     *     return match[2] == 'gt' ? object[match[1]] > match[3] : object[match[1]] < match[3];
     *   };
     * });
     *
     * _.filter(characters, 'age__gt38');
     * // => [{ 'name': 'fred', 'age': 40 }]
     */
    function createCallback(func, thisArg, argCount) {
      var type = typeof func;
      if (func == null || type == 'function') {
        return baseCreateCallback(func, thisArg, argCount);
      }
      // handle "_.pluck" style callback shorthands
      if (type != 'object') {
        return property(func);
      }
      var props = keys(func),
          key = props[0],
          a = func[key];

      // handle "_.where" style callback shorthands
      if (props.length == 1 && a === a && !isObject(a)) {
        // fast path the common case of providing an object with a single
        // property containing a primitive value
        return function(object) {
          var b = object[key];
          return a === b && (a !== 0 || (1 / a == 1 / b));
        };
      }
      return function(object) {
        var length = props.length,
            result = false;

        while (length--) {
          if (!(result = baseIsEqual(object[props[length]], func[props[length]], null, true))) {
            break;
          }
        }
        return result;
      };
    }

    /**
     * Converts the characters `&`, `<`, `>`, `"`, and `'` in `string` to their
     * corresponding HTML entities.
     *
     * @static
     * @memberOf _
     * @category Utilities
     * @param {string} string The string to escape.
     * @returns {string} Returns the escaped string.
     * @example
     *
     * _.escape('Fred, Wilma, & Pebbles');
     * // => 'Fred, Wilma, &amp; Pebbles'
     */
    function escape(string) {
      return string == null ? '' : String(string).replace(reUnescapedHtml, escapeHtmlChar);
    }

    /**
     * This method returns the first argument provided to it.
     *
     * @static
     * @memberOf _
     * @category Utilities
     * @param {*} value Any value.
     * @returns {*} Returns `value`.
     * @example
     *
     * var object = { 'name': 'fred' };
     * _.identity(object) === object;
     * // => true
     */
    function identity(value) {
      return value;
    }

    /**
     * Adds function properties of a source object to the destination object.
     * If `object` is a function methods will be added to its prototype as well.
     *
     * @static
     * @memberOf _
     * @category Utilities
     * @param {Function|Object} [object=lodash] object The destination object.
     * @param {Object} source The object of functions to add.
     * @param {Object} [options] The options object.
     * @param {boolean} [options.chain=true] Specify whether the functions added are chainable.
     * @example
     *
     * function capitalize(string) {
     *   return string.charAt(0).toUpperCase() + string.slice(1).toLowerCase();
     * }
     *
     * _.mixin({ 'capitalize': capitalize });
     * _.capitalize('fred');
     * // => 'Fred'
     *
     * _('fred').capitalize().value();
     * // => 'Fred'
     *
     * _.mixin({ 'capitalize': capitalize }, { 'chain': false });
     * _('fred').capitalize();
     * // => 'Fred'
     */
    function mixin(object, source, options) {
      var chain = true,
          methodNames = source && functions(source);

      if (!source || (!options && !methodNames.length)) {
        if (options == null) {
          options = source;
        }
        ctor = lodashWrapper;
        source = object;
        object = lodash;
        methodNames = functions(source);
      }
      if (options === false) {
        chain = false;
      } else if (isObject(options) && 'chain' in options) {
        chain = options.chain;
      }
      var ctor = object,
          isFunc = isFunction(ctor);

      forEach(methodNames, function(methodName) {
        var func = object[methodName] = source[methodName];
        if (isFunc) {
          ctor.prototype[methodName] = function() {
            var chainAll = this.__chain__,
                value = this.__wrapped__,
                args = [value];

            push.apply(args, arguments);
            var result = func.apply(object, args);
            if (chain || chainAll) {
              if (value === result && isObject(result)) {
                return this;
              }
              result = new ctor(result);
              result.__chain__ = chainAll;
            }
            return result;
          };
        }
      });
    }

    /**
     * Reverts the '_' variable to its previous value and returns a reference to
     * the `lodash` function.
     *
     * @static
     * @memberOf _
     * @category Utilities
     * @returns {Function} Returns the `lodash` function.
     * @example
     *
     * var lodash = _.noConflict();
     */
    function noConflict() {
      context._ = oldDash;
      return this;
    }

    /**
     * A no-operation function.
     *
     * @static
     * @memberOf _
     * @category Utilities
     * @example
     *
     * var object = { 'name': 'fred' };
     * _.noop(object) === undefined;
     * // => true
     */
    function noop() {
      // no operation performed
    }

    /**
     * Gets the number of milliseconds that have elapsed since the Unix epoch
     * (1 January 1970 00:00:00 UTC).
     *
     * @static
     * @memberOf _
     * @category Utilities
     * @example
     *
     * var stamp = _.now();
     * _.defer(function() { console.log(_.now() - stamp); });
     * // => logs the number of milliseconds it took for the deferred function to be called
     */
    var now = isNative(now = Date.now) && now || function() {
      return new Date().getTime();
    };

    /**
     * Converts the given value into an integer of the specified radix.
     * If `radix` is `undefined` or `0` a `radix` of `10` is used unless the
     * `value` is a hexadecimal, in which case a `radix` of `16` is used.
     *
     * Note: This method avoids differences in native ES3 and ES5 `parseInt`
     * implementations. See http://es5.github.io/#E.
     *
     * @static
     * @memberOf _
     * @category Utilities
     * @param {string} value The value to parse.
     * @param {number} [radix] The radix used to interpret the value to parse.
     * @returns {number} Returns the new integer value.
     * @example
     *
     * _.parseInt('08');
     * // => 8
     */
    var parseInt = nativeParseInt(whitespace + '08') == 8 ? nativeParseInt : function(value, radix) {
      // Firefox < 21 and Opera < 15 follow the ES3 specified implementation of `parseInt`
      return nativeParseInt(isString(value) ? value.replace(reLeadingSpacesAndZeros, '') : value, radix || 0);
    };

    /**
     * Creates a "_.pluck" style function, which returns the `key` value of a
     * given object.
     *
     * @static
     * @memberOf _
     * @category Utilities
     * @param {string} key The name of the property to retrieve.
     * @returns {Function} Returns the new function.
     * @example
     *
     * var characters = [
     *   { 'name': 'fred',   'age': 40 },
     *   { 'name': 'barney', 'age': 36 }
     * ];
     *
     * var getName = _.property('name');
     *
     * _.map(characters, getName);
     * // => ['barney', 'fred']
     *
     * _.sortBy(characters, getName);
     * // => [{ 'name': 'barney', 'age': 36 }, { 'name': 'fred',   'age': 40 }]
     */
    function property(key) {
      return function(object) {
        return object[key];
      };
    }

    /**
     * Produces a random number between `min` and `max` (inclusive). If only one
     * argument is provided a number between `0` and the given number will be
     * returned. If `floating` is truey or either `min` or `max` are floats a
     * floating-point number will be returned instead of an integer.
     *
     * @static
     * @memberOf _
     * @category Utilities
     * @param {number} [min=0] The minimum possible value.
     * @param {number} [max=1] The maximum possible value.
     * @param {boolean} [floating=false] Specify returning a floating-point number.
     * @returns {number} Returns a random number.
     * @example
     *
     * _.random(0, 5);
     * // => an integer between 0 and 5
     *
     * _.random(5);
     * // => also an integer between 0 and 5
     *
     * _.random(5, true);
     * // => a floating-point number between 0 and 5
     *
     * _.random(1.2, 5.2);
     * // => a floating-point number between 1.2 and 5.2
     */
    function random(min, max, floating) {
      var noMin = min == null,
          noMax = max == null;

      if (floating == null) {
        if (typeof min == 'boolean' && noMax) {
          floating = min;
          min = 1;
        }
        else if (!noMax && typeof max == 'boolean') {
          floating = max;
          noMax = true;
        }
      }
      if (noMin && noMax) {
        max = 1;
      }
      min = +min || 0;
      if (noMax) {
        max = min;
        min = 0;
      } else {
        max = +max || 0;
      }
      if (floating || min % 1 || max % 1) {
        var rand = nativeRandom();
        return nativeMin(min + (rand * (max - min + parseFloat('1e-' + ((rand +'').length - 1)))), max);
      }
      return baseRandom(min, max);
    }

    /**
     * Resolves the value of property `key` on `object`. If `key` is a function
     * it will be invoked with the `this` binding of `object` and its result returned,
     * else the property value is returned. If `object` is falsey then `undefined`
     * is returned.
     *
     * @static
     * @memberOf _
     * @category Utilities
     * @param {Object} object The object to inspect.
     * @param {string} key The name of the property to resolve.
     * @returns {*} Returns the resolved value.
     * @example
     *
     * var object = {
     *   'cheese': 'crumpets',
     *   'stuff': function() {
     *     return 'nonsense';
     *   }
     * };
     *
     * _.result(object, 'cheese');
     * // => 'crumpets'
     *
     * _.result(object, 'stuff');
     * // => 'nonsense'
     */
    function result(object, key) {
      if (object) {
        var value = object[key];
        return isFunction(value) ? object[key]() : value;
      }
    }

    /**
     * A micro-templating method that handles arbitrary delimiters, preserves
     * whitespace, and correctly escapes quotes within interpolated code.
     *
     * Note: In the development build, `_.template` utilizes sourceURLs for easier
     * debugging. See http://www.html5rocks.com/en/tutorials/developertools/sourcemaps/#toc-sourceurl
     *
     * For more information on precompiling templates see:
     * http://lodash.com/custom-builds
     *
     * For more information on Chrome extension sandboxes see:
     * http://developer.chrome.com/stable/extensions/sandboxingEval.html
     *
     * @static
     * @memberOf _
     * @category Utilities
     * @param {string} text The template text.
     * @param {Object} data The data object used to populate the text.
     * @param {Object} [options] The options object.
     * @param {RegExp} [options.escape] The "escape" delimiter.
     * @param {RegExp} [options.evaluate] The "evaluate" delimiter.
     * @param {Object} [options.imports] An object to import into the template as local variables.
     * @param {RegExp} [options.interpolate] The "interpolate" delimiter.
     * @param {string} [sourceURL] The sourceURL of the template's compiled source.
     * @param {string} [variable] The data object variable name.
     * @returns {Function|string} Returns a compiled function when no `data` object
     *  is given, else it returns the interpolated text.
     * @example
     *
     * // using the "interpolate" delimiter to create a compiled template
     * var compiled = _.template('hello <%= name %>');
     * compiled({ 'name': 'fred' });
     * // => 'hello fred'
     *
     * // using the "escape" delimiter to escape HTML in data property values
     * _.template('<b><%- value %></b>', { 'value': '<script>' });
     * // => '<b>&lt;script&gt;</b>'
     *
     * // using the "evaluate" delimiter to generate HTML
     * var list = '<% _.forEach(people, function(name) { %><li><%- name %></li><% }); %>';
     * _.template(list, { 'people': ['fred', 'barney'] });
     * // => '<li>fred</li><li>barney</li>'
     *
     * // using the ES6 delimiter as an alternative to the default "interpolate" delimiter
     * _.template('hello ${ name }', { 'name': 'pebbles' });
     * // => 'hello pebbles'
     *
     * // using the internal `print` function in "evaluate" delimiters
     * _.template('<% print("hello " + name); %>!', { 'name': 'barney' });
     * // => 'hello barney!'
     *
     * // using a custom template delimiters
     * _.templateSettings = {
     *   'interpolate': /{{([\s\S]+?)}}/g
     * };
     *
     * _.template('hello {{ name }}!', { 'name': 'mustache' });
     * // => 'hello mustache!'
     *
     * // using the `imports` option to import jQuery
     * var list = '<% jq.each(people, function(name) { %><li><%- name %></li><% }); %>';
     * _.template(list, { 'people': ['fred', 'barney'] }, { 'imports': { 'jq': jQuery } });
     * // => '<li>fred</li><li>barney</li>'
     *
     * // using the `sourceURL` option to specify a custom sourceURL for the template
     * var compiled = _.template('hello <%= name %>', null, { 'sourceURL': '/basic/greeting.jst' });
     * compiled(data);
     * // => find the source of "greeting.jst" under the Sources tab or Resources panel of the web inspector
     *
     * // using the `variable` option to ensure a with-statement isn't used in the compiled template
     * var compiled = _.template('hi <%= data.name %>!', null, { 'variable': 'data' });
     * compiled.source;
     * // => function(data) {
     *   var __t, __p = '', __e = _.escape;
     *   __p += 'hi ' + ((__t = ( data.name )) == null ? '' : __t) + '!';
     *   return __p;
     * }
     *
     * // using the `source` property to inline compiled templates for meaningful
     * // line numbers in error messages and a stack trace
     * fs.writeFileSync(path.join(cwd, 'jst.js'), '\
     *   var JST = {\
     *     "main": ' + _.template(mainText).source + '\
     *   };\
     * ');
     */
    function template(text, data, options) {
      // based on John Resig's `tmpl` implementation
      // http://ejohn.org/blog/javascript-micro-templating/
      // and Laura Doktorova's doT.js
      // https://github.com/olado/doT
      var settings = lodash.templateSettings;
      text = String(text || '');

      // avoid missing dependencies when `iteratorTemplate` is not defined
      options = defaults({}, options, settings);

      var imports = defaults({}, options.imports, settings.imports),
          importsKeys = keys(imports),
          importsValues = values(imports);

      var isEvaluating,
          index = 0,
          interpolate = options.interpolate || reNoMatch,
          source = "__p += '";

      // compile the regexp to match each delimiter
      var reDelimiters = RegExp(
        (options.escape || reNoMatch).source + '|' +
        interpolate.source + '|' +
        (interpolate === reInterpolate ? reEsTemplate : reNoMatch).source + '|' +
        (options.evaluate || reNoMatch).source + '|$'
      , 'g');

      text.replace(reDelimiters, function(match, escapeValue, interpolateValue, esTemplateValue, evaluateValue, offset) {
        interpolateValue || (interpolateValue = esTemplateValue);

        // escape characters that cannot be included in string literals
        source += text.slice(index, offset).replace(reUnescapedString, escapeStringChar);

        // replace delimiters with snippets
        if (escapeValue) {
          source += "' +\n__e(" + escapeValue + ") +\n'";
        }
        if (evaluateValue) {
          isEvaluating = true;
          source += "';\n" + evaluateValue + ";\n__p += '";
        }
        if (interpolateValue) {
          source += "' +\n((__t = (" + interpolateValue + ")) == null ? '' : __t) +\n'";
        }
        index = offset + match.length;

        // the JS engine embedded in Adobe products requires returning the `match`
        // string in order to produce the correct `offset` value
        return match;
      });

      source += "';\n";

      // if `variable` is not specified, wrap a with-statement around the generated
      // code to add the data object to the top of the scope chain
      var variable = options.variable,
          hasVariable = variable;

      if (!hasVariable) {
        variable = 'obj';
        source = 'with (' + variable + ') {\n' + source + '\n}\n';
      }
      // cleanup code by stripping empty strings
      source = (isEvaluating ? source.replace(reEmptyStringLeading, '') : source)
        .replace(reEmptyStringMiddle, '$1')
        .replace(reEmptyStringTrailing, '$1;');

      // frame code as the function body
      source = 'function(' + variable + ') {\n' +
        (hasVariable ? '' : variable + ' || (' + variable + ' = {});\n') +
        "var __t, __p = '', __e = _.escape" +
        (isEvaluating
          ? ', __j = Array.prototype.join;\n' +
            "function print() { __p += __j.call(arguments, '') }\n"
          : ';\n'
        ) +
        source +
        'return __p\n}';

      // Use a sourceURL for easier debugging.
      // http://www.html5rocks.com/en/tutorials/developertools/sourcemaps/#toc-sourceurl
      var sourceURL = '\n/*\n//# sourceURL=' + (options.sourceURL || '/lodash/template/source[' + (templateCounter++) + ']') + '\n*/';

      try {
        var result = Function(importsKeys, 'return ' + source + sourceURL).apply(undefined, importsValues);
      } catch(e) {
        e.source = source;
        throw e;
      }
      if (data) {
        return result(data);
      }
      // provide the compiled function's source by its `toString` method, in
      // supported environments, or the `source` property as a convenience for
      // inlining compiled templates during the build process
      result.source = source;
      return result;
    }

    /**
     * Executes the callback `n` times, returning an array of the results
     * of each callback execution. The callback is bound to `thisArg` and invoked
     * with one argument; (index).
     *
     * @static
     * @memberOf _
     * @category Utilities
     * @param {number} n The number of times to execute the callback.
     * @param {Function} callback The function called per iteration.
     * @param {*} [thisArg] The `this` binding of `callback`.
     * @returns {Array} Returns an array of the results of each `callback` execution.
     * @example
     *
     * var diceRolls = _.times(3, _.partial(_.random, 1, 6));
     * // => [3, 6, 4]
     *
     * _.times(3, function(n) { mage.castSpell(n); });
     * // => calls `mage.castSpell(n)` three times, passing `n` of `0`, `1`, and `2` respectively
     *
     * _.times(3, function(n) { this.cast(n); }, mage);
     * // => also calls `mage.castSpell(n)` three times
     */
    function times(n, callback, thisArg) {
      n = (n = +n) > -1 ? n : 0;
      var index = -1,
          result = Array(n);

      callback = baseCreateCallback(callback, thisArg, 1);
      while (++index < n) {
        result[index] = callback(index);
      }
      return result;
    }

    /**
     * The inverse of `_.escape` this method converts the HTML entities
     * `&amp;`, `&lt;`, `&gt;`, `&quot;`, and `&#39;` in `string` to their
     * corresponding characters.
     *
     * @static
     * @memberOf _
     * @category Utilities
     * @param {string} string The string to unescape.
     * @returns {string} Returns the unescaped string.
     * @example
     *
     * _.unescape('Fred, Barney &amp; Pebbles');
     * // => 'Fred, Barney & Pebbles'
     */
    function unescape(string) {
      return string == null ? '' : String(string).replace(reEscapedHtml, unescapeHtmlChar);
    }

    /**
     * Generates a unique ID. If `prefix` is provided the ID will be appended to it.
     *
     * @static
     * @memberOf _
     * @category Utilities
     * @param {string} [prefix] The value to prefix the ID with.
     * @returns {string} Returns the unique ID.
     * @example
     *
     * _.uniqueId('contact_');
     * // => 'contact_104'
     *
     * _.uniqueId();
     * // => '105'
     */
    function uniqueId(prefix) {
      var id = ++idCounter;
      return String(prefix == null ? '' : prefix) + id;
    }

    /*--------------------------------------------------------------------------*/

    /**
     * Creates a `lodash` object that wraps the given value with explicit
     * method chaining enabled.
     *
     * @static
     * @memberOf _
     * @category Chaining
     * @param {*} value The value to wrap.
     * @returns {Object} Returns the wrapper object.
     * @example
     *
     * var characters = [
     *   { 'name': 'barney',  'age': 36 },
     *   { 'name': 'fred',    'age': 40 },
     *   { 'name': 'pebbles', 'age': 1 }
     * ];
     *
     * var youngest = _.chain(characters)
     *     .sortBy('age')
     *     .map(function(chr) { return chr.name + ' is ' + chr.age; })
     *     .first()
     *     .value();
     * // => 'pebbles is 1'
     */
    function chain(value) {
      value = new lodashWrapper(value);
      value.__chain__ = true;
      return value;
    }

    /**
     * Invokes `interceptor` with the `value` as the first argument and then
     * returns `value`. The purpose of this method is to "tap into" a method
     * chain in order to perform operations on intermediate results within
     * the chain.
     *
     * @static
     * @memberOf _
     * @category Chaining
     * @param {*} value The value to provide to `interceptor`.
     * @param {Function} interceptor The function to invoke.
     * @returns {*} Returns `value`.
     * @example
     *
     * _([1, 2, 3, 4])
     *  .tap(function(array) { array.pop(); })
     *  .reverse()
     *  .value();
     * // => [3, 2, 1]
     */
    function tap(value, interceptor) {
      interceptor(value);
      return value;
    }

    /**
     * Enables explicit method chaining on the wrapper object.
     *
     * @name chain
     * @memberOf _
     * @category Chaining
     * @returns {*} Returns the wrapper object.
     * @example
     *
     * var characters = [
     *   { 'name': 'barney', 'age': 36 },
     *   { 'name': 'fred',   'age': 40 }
     * ];
     *
     * // without explicit chaining
     * _(characters).first();
     * // => { 'name': 'barney', 'age': 36 }
     *
     * // with explicit chaining
     * _(characters).chain()
     *   .first()
     *   .pick('age')
     *   .value();
     * // => { 'age': 36 }
     */
    function wrapperChain() {
      this.__chain__ = true;
      return this;
    }

    /**
     * Produces the `toString` result of the wrapped value.
     *
     * @name toString
     * @memberOf _
     * @category Chaining
     * @returns {string} Returns the string result.
     * @example
     *
     * _([1, 2, 3]).toString();
     * // => '1,2,3'
     */
    function wrapperToString() {
      return String(this.__wrapped__);
    }

    /**
     * Extracts the wrapped value.
     *
     * @name valueOf
     * @memberOf _
     * @alias value
     * @category Chaining
     * @returns {*} Returns the wrapped value.
     * @example
     *
     * _([1, 2, 3]).valueOf();
     * // => [1, 2, 3]
     */
    function wrapperValueOf() {
      return this.__wrapped__;
    }

    /*--------------------------------------------------------------------------*/

    // add functions that return wrapped values when chaining
    lodash.after = after;
    lodash.assign = assign;
    lodash.at = at;
    lodash.bind = bind;
    lodash.bindAll = bindAll;
    lodash.bindKey = bindKey;
    lodash.chain = chain;
    lodash.compact = compact;
    lodash.compose = compose;
    lodash.constant = constant;
    lodash.countBy = countBy;
    lodash.create = create;
    lodash.createCallback = createCallback;
    lodash.curry = curry;
    lodash.debounce = debounce;
    lodash.defaults = defaults;
    lodash.defer = defer;
    lodash.delay = delay;
    lodash.difference = difference;
    lodash.filter = filter;
    lodash.flatten = flatten;
    lodash.forEach = forEach;
    lodash.forEachRight = forEachRight;
    lodash.forIn = forIn;
    lodash.forInRight = forInRight;
    lodash.forOwn = forOwn;
    lodash.forOwnRight = forOwnRight;
    lodash.functions = functions;
    lodash.groupBy = groupBy;
    lodash.indexBy = indexBy;
    lodash.initial = initial;
    lodash.intersection = intersection;
    lodash.invert = invert;
    lodash.invoke = invoke;
    lodash.keys = keys;
    lodash.map = map;
    lodash.mapValues = mapValues;
    lodash.max = max;
    lodash.memoize = memoize;
    lodash.merge = merge;
    lodash.min = min;
    lodash.omit = omit;
    lodash.once = once;
    lodash.pairs = pairs;
    lodash.partial = partial;
    lodash.partialRight = partialRight;
    lodash.pick = pick;
    lodash.pluck = pluck;
    lodash.property = property;
    lodash.pull = pull;
    lodash.range = range;
    lodash.reject = reject;
    lodash.remove = remove;
    lodash.rest = rest;
    lodash.shuffle = shuffle;
    lodash.sortBy = sortBy;
    lodash.tap = tap;
    lodash.throttle = throttle;
    lodash.times = times;
    lodash.toArray = toArray;
    lodash.transform = transform;
    lodash.union = union;
    lodash.uniq = uniq;
    lodash.values = values;
    lodash.where = where;
    lodash.without = without;
    lodash.wrap = wrap;
    lodash.xor = xor;
    lodash.zip = zip;
    lodash.zipObject = zipObject;

    // add aliases
    lodash.collect = map;
    lodash.drop = rest;
    lodash.each = forEach;
    lodash.eachRight = forEachRight;
    lodash.extend = assign;
    lodash.methods = functions;
    lodash.object = zipObject;
    lodash.select = filter;
    lodash.tail = rest;
    lodash.unique = uniq;
    lodash.unzip = zip;

    // add functions to `lodash.prototype`
    mixin(lodash);

    /*--------------------------------------------------------------------------*/

    // add functions that return unwrapped values when chaining
    lodash.clone = clone;
    lodash.cloneDeep = cloneDeep;
    lodash.contains = contains;
    lodash.escape = escape;
    lodash.every = every;
    lodash.find = find;
    lodash.findIndex = findIndex;
    lodash.findKey = findKey;
    lodash.findLast = findLast;
    lodash.findLastIndex = findLastIndex;
    lodash.findLastKey = findLastKey;
    lodash.has = has;
    lodash.identity = identity;
    lodash.indexOf = indexOf;
    lodash.isArguments = isArguments;
    lodash.isArray = isArray;
    lodash.isBoolean = isBoolean;
    lodash.isDate = isDate;
    lodash.isElement = isElement;
    lodash.isEmpty = isEmpty;
    lodash.isEqual = isEqual;
    lodash.isFinite = isFinite;
    lodash.isFunction = isFunction;
    lodash.isNaN = isNaN;
    lodash.isNull = isNull;
    lodash.isNumber = isNumber;
    lodash.isObject = isObject;
    lodash.isPlainObject = isPlainObject;
    lodash.isRegExp = isRegExp;
    lodash.isString = isString;
    lodash.isUndefined = isUndefined;
    lodash.lastIndexOf = lastIndexOf;
    lodash.mixin = mixin;
    lodash.noConflict = noConflict;
    lodash.noop = noop;
    lodash.now = now;
    lodash.parseInt = parseInt;
    lodash.random = random;
    lodash.reduce = reduce;
    lodash.reduceRight = reduceRight;
    lodash.result = result;
    lodash.runInContext = runInContext;
    lodash.size = size;
    lodash.some = some;
    lodash.sortedIndex = sortedIndex;
    lodash.template = template;
    lodash.unescape = unescape;
    lodash.uniqueId = uniqueId;

    // add aliases
    lodash.all = every;
    lodash.any = some;
    lodash.detect = find;
    lodash.findWhere = find;
    lodash.foldl = reduce;
    lodash.foldr = reduceRight;
    lodash.include = contains;
    lodash.inject = reduce;

    mixin(function() {
      var source = {}
      forOwn(lodash, function(func, methodName) {
        if (!lodash.prototype[methodName]) {
          source[methodName] = func;
        }
      });
      return source;
    }(), false);

    /*--------------------------------------------------------------------------*/

    // add functions capable of returning wrapped and unwrapped values when chaining
    lodash.first = first;
    lodash.last = last;
    lodash.sample = sample;

    // add aliases
    lodash.take = first;
    lodash.head = first;

    forOwn(lodash, function(func, methodName) {
      var callbackable = methodName !== 'sample';
      if (!lodash.prototype[methodName]) {
        lodash.prototype[methodName]= function(n, guard) {
          var chainAll = this.__chain__,
              result = func(this.__wrapped__, n, guard);

          return !chainAll && (n == null || (guard && !(callbackable && typeof n == 'function')))
            ? result
            : new lodashWrapper(result, chainAll);
        };
      }
    });

    /*--------------------------------------------------------------------------*/

    /**
     * The semantic version number.
     *
     * @static
     * @memberOf _
     * @type string
     */
    lodash.VERSION = '2.4.1';

    // add "Chaining" functions to the wrapper
    lodash.prototype.chain = wrapperChain;
    lodash.prototype.toString = wrapperToString;
    lodash.prototype.value = wrapperValueOf;
    lodash.prototype.valueOf = wrapperValueOf;

    // add `Array` functions that return unwrapped values
    baseEach(['join', 'pop', 'shift'], function(methodName) {
      var func = arrayRef[methodName];
      lodash.prototype[methodName] = function() {
        var chainAll = this.__chain__,
            result = func.apply(this.__wrapped__, arguments);

        return chainAll
          ? new lodashWrapper(result, chainAll)
          : result;
      };
    });

    // add `Array` functions that return the existing wrapped value
    baseEach(['push', 'reverse', 'sort', 'unshift'], function(methodName) {
      var func = arrayRef[methodName];
      lodash.prototype[methodName] = function() {
        func.apply(this.__wrapped__, arguments);
        return this;
      };
    });

    // add `Array` functions that return new wrapped values
    baseEach(['concat', 'slice', 'splice'], function(methodName) {
      var func = arrayRef[methodName];
      lodash.prototype[methodName] = function() {
        return new lodashWrapper(func.apply(this.__wrapped__, arguments), this.__chain__);
      };
    });

    // avoid array-like object bugs with `Array#shift` and `Array#splice`
    // in IE < 9, Firefox < 10, Narwhal, and RingoJS
    if (!support.spliceObjects) {
      baseEach(['pop', 'shift', 'splice'], function(methodName) {
        var func = arrayRef[methodName],
            isSplice = methodName == 'splice';

        lodash.prototype[methodName] = function() {
          var chainAll = this.__chain__,
              value = this.__wrapped__,
              result = func.apply(value, arguments);

          if (value.length === 0) {
            delete value[0];
          }
          return (chainAll || isSplice)
            ? new lodashWrapper(result, chainAll)
            : result;
        };
      });
    }

    return lodash;
  }

  /*--------------------------------------------------------------------------*/

  // expose Lo-Dash
  var _ = runInContext();

  // some AMD build optimizers like r.js check for condition patterns like the following:
  if (typeof define == 'function' && typeof define.amd == 'object' && define.amd) {
    // Expose Lo-Dash to the global object even when an AMD loader is present in
    // case Lo-Dash is loaded with a RequireJS shim config.
    // See http://requirejs.org/docs/api.html#config-shim
    root._ = _;

    // define as an anonymous module so, through path mapping, it can be
    // referenced as the "underscore" module
    define(function() {
      return _;
    });
  }
  // check for `exports` after `define` in case a build optimizer adds an `exports` object
  else if (freeExports && freeModule) {
    // in Node.js or RingoJS
    if (moduleExports) {
      (freeModule.exports = _)._ = _;
    }
    // in Narwhal or Rhino -require
    else {
      freeExports._ = _;
    }
  }
  else {
    // in a browser or Rhino
    root._ = _;
  }
}.call(this));

//! moment.js
//! version : 2.8.1
//! authors : Tim Wood, Iskren Chernev, Moment.js contributors
//! license : MIT
//! momentjs.com

(function (undefined) {
    /************************************
        Constants
    ************************************/

    var moment,
        VERSION = '2.8.1',
        // the global-scope this is NOT the global object in Node.js
        globalScope = typeof global !== 'undefined' ? global : this,
        oldGlobalMoment,
        round = Math.round,
        i,

        YEAR = 0,
        MONTH = 1,
        DATE = 2,
        HOUR = 3,
        MINUTE = 4,
        SECOND = 5,
        MILLISECOND = 6,

        // internal storage for locale config files
        locales = {},

        // extra moment internal properties (plugins register props here)
        momentProperties = [],

        // check for nodeJS
        hasModule = (typeof module !== 'undefined' && module.exports),

        // ASP.NET json date format regex
        aspNetJsonRegex = /^\/?Date\((\-?\d+)/i,
        aspNetTimeSpanJsonRegex = /(\-)?(?:(\d*)\.)?(\d+)\:(\d+)(?:\:(\d+)\.?(\d{3})?)?/,

        // from http://docs.closure-library.googlecode.com/git/closure_goog_date_date.js.source.html
        // somewhat more in line with 4.4.3.2 2004 spec, but allows decimal anywhere
        isoDurationRegex = /^(-)?P(?:(?:([0-9,.]*)Y)?(?:([0-9,.]*)M)?(?:([0-9,.]*)D)?(?:T(?:([0-9,.]*)H)?(?:([0-9,.]*)M)?(?:([0-9,.]*)S)?)?|([0-9,.]*)W)$/,

        // format tokens
        formattingTokens = /(\[[^\[]*\])|(\\)?(Mo|MM?M?M?|Do|DDDo|DD?D?D?|ddd?d?|do?|w[o|w]?|W[o|W]?|Q|YYYYYY|YYYYY|YYYY|YY|gg(ggg?)?|GG(GGG?)?|e|E|a|A|hh?|HH?|mm?|ss?|S{1,4}|X|zz?|ZZ?|.)/g,
        localFormattingTokens = /(\[[^\[]*\])|(\\)?(LT|LL?L?L?|l{1,4})/g,

        // parsing token regexes
        parseTokenOneOrTwoDigits = /\d\d?/, // 0 - 99
        parseTokenOneToThreeDigits = /\d{1,3}/, // 0 - 999
        parseTokenOneToFourDigits = /\d{1,4}/, // 0 - 9999
        parseTokenOneToSixDigits = /[+\-]?\d{1,6}/, // -999,999 - 999,999
        parseTokenDigits = /\d+/, // nonzero number of digits
        parseTokenWord = /[0-9]*['a-z\u00A0-\u05FF\u0700-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF]+|[\u0600-\u06FF\/]+(\s*?[\u0600-\u06FF]+){1,2}/i, // any word (or two) characters or numbers including two/three word month in arabic.
        parseTokenTimezone = /Z|[\+\-]\d\d:?\d\d/gi, // +00:00 -00:00 +0000 -0000 or Z
        parseTokenT = /T/i, // T (ISO separator)
        parseTokenTimestampMs = /[\+\-]?\d+(\.\d{1,3})?/, // 123456789 123456789.123
        parseTokenOrdinal = /\d{1,2}/,

        //strict parsing regexes
        parseTokenOneDigit = /\d/, // 0 - 9
        parseTokenTwoDigits = /\d\d/, // 00 - 99
        parseTokenThreeDigits = /\d{3}/, // 000 - 999
        parseTokenFourDigits = /\d{4}/, // 0000 - 9999
        parseTokenSixDigits = /[+-]?\d{6}/, // -999,999 - 999,999
        parseTokenSignedNumber = /[+-]?\d+/, // -inf - inf

        // iso 8601 regex
        // 0000-00-00 0000-W00 or 0000-W00-0 + T + 00 or 00:00 or 00:00:00 or 00:00:00.000 + +00:00 or +0000 or +00)
        isoRegex = /^\s*(?:[+-]\d{6}|\d{4})-(?:(\d\d-\d\d)|(W\d\d$)|(W\d\d-\d)|(\d\d\d))((T| )(\d\d(:\d\d(:\d\d(\.\d+)?)?)?)?([\+\-]\d\d(?::?\d\d)?|\s*Z)?)?$/,

        isoFormat = 'YYYY-MM-DDTHH:mm:ssZ',

        isoDates = [
            ['YYYYYY-MM-DD', /[+-]\d{6}-\d{2}-\d{2}/],
            ['YYYY-MM-DD', /\d{4}-\d{2}-\d{2}/],
            ['GGGG-[W]WW-E', /\d{4}-W\d{2}-\d/],
            ['GGGG-[W]WW', /\d{4}-W\d{2}/],
            ['YYYY-DDD', /\d{4}-\d{3}/]
        ],

        // iso time formats and regexes
        isoTimes = [
            ['HH:mm:ss.SSSS', /(T| )\d\d:\d\d:\d\d\.\d+/],
            ['HH:mm:ss', /(T| )\d\d:\d\d:\d\d/],
            ['HH:mm', /(T| )\d\d:\d\d/],
            ['HH', /(T| )\d\d/]
        ],

        // timezone chunker "+10:00" > ["10", "00"] or "-1530" > ["-15", "30"]
        parseTimezoneChunker = /([\+\-]|\d\d)/gi,

        // getter and setter names
        proxyGettersAndSetters = 'Date|Hours|Minutes|Seconds|Milliseconds'.split('|'),
        unitMillisecondFactors = {
            'Milliseconds' : 1,
            'Seconds' : 1e3,
            'Minutes' : 6e4,
            'Hours' : 36e5,
            'Days' : 864e5,
            'Months' : 2592e6,
            'Years' : 31536e6
        },

        unitAliases = {
            ms : 'millisecond',
            s : 'second',
            m : 'minute',
            h : 'hour',
            d : 'day',
            D : 'date',
            w : 'week',
            W : 'isoWeek',
            M : 'month',
            Q : 'quarter',
            y : 'year',
            DDD : 'dayOfYear',
            e : 'weekday',
            E : 'isoWeekday',
            gg: 'weekYear',
            GG: 'isoWeekYear'
        },

        camelFunctions = {
            dayofyear : 'dayOfYear',
            isoweekday : 'isoWeekday',
            isoweek : 'isoWeek',
            weekyear : 'weekYear',
            isoweekyear : 'isoWeekYear'
        },

        // format function strings
        formatFunctions = {},

        // default relative time thresholds
        relativeTimeThresholds = {
            s: 45,  // seconds to minute
            m: 45,  // minutes to hour
            h: 22,  // hours to day
            d: 26,  // days to month
            M: 11   // months to year
        },

        // tokens to ordinalize and pad
        ordinalizeTokens = 'DDD w W M D d'.split(' '),
        paddedTokens = 'M D H h m s w W'.split(' '),

        formatTokenFunctions = {
            M    : function () {
                return this.month() + 1;
            },
            MMM  : function (format) {
                return this.localeData().monthsShort(this, format);
            },
            MMMM : function (format) {
                return this.localeData().months(this, format);
            },
            D    : function () {
                return this.date();
            },
            DDD  : function () {
                return this.dayOfYear();
            },
            d    : function () {
                return this.day();
            },
            dd   : function (format) {
                return this.localeData().weekdaysMin(this, format);
            },
            ddd  : function (format) {
                return this.localeData().weekdaysShort(this, format);
            },
            dddd : function (format) {
                return this.localeData().weekdays(this, format);
            },
            w    : function () {
                return this.week();
            },
            W    : function () {
                return this.isoWeek();
            },
            YY   : function () {
                return leftZeroFill(this.year() % 100, 2);
            },
            YYYY : function () {
                return leftZeroFill(this.year(), 4);
            },
            YYYYY : function () {
                return leftZeroFill(this.year(), 5);
            },
            YYYYYY : function () {
                var y = this.year(), sign = y >= 0 ? '+' : '-';
                return sign + leftZeroFill(Math.abs(y), 6);
            },
            gg   : function () {
                return leftZeroFill(this.weekYear() % 100, 2);
            },
            gggg : function () {
                return leftZeroFill(this.weekYear(), 4);
            },
            ggggg : function () {
                return leftZeroFill(this.weekYear(), 5);
            },
            GG   : function () {
                return leftZeroFill(this.isoWeekYear() % 100, 2);
            },
            GGGG : function () {
                return leftZeroFill(this.isoWeekYear(), 4);
            },
            GGGGG : function () {
                return leftZeroFill(this.isoWeekYear(), 5);
            },
            e : function () {
                return this.weekday();
            },
            E : function () {
                return this.isoWeekday();
            },
            a    : function () {
                return this.localeData().meridiem(this.hours(), this.minutes(), true);
            },
            A    : function () {
                return this.localeData().meridiem(this.hours(), this.minutes(), false);
            },
            H    : function () {
                return this.hours();
            },
            h    : function () {
                return this.hours() % 12 || 12;
            },
            m    : function () {
                return this.minutes();
            },
            s    : function () {
                return this.seconds();
            },
            S    : function () {
                return toInt(this.milliseconds() / 100);
            },
            SS   : function () {
                return leftZeroFill(toInt(this.milliseconds() / 10), 2);
            },
            SSS  : function () {
                return leftZeroFill(this.milliseconds(), 3);
            },
            SSSS : function () {
                return leftZeroFill(this.milliseconds(), 3);
            },
            Z    : function () {
                var a = -this.zone(),
                    b = '+';
                if (a < 0) {
                    a = -a;
                    b = '-';
                }
                return b + leftZeroFill(toInt(a / 60), 2) + ':' + leftZeroFill(toInt(a) % 60, 2);
            },
            ZZ   : function () {
                var a = -this.zone(),
                    b = '+';
                if (a < 0) {
                    a = -a;
                    b = '-';
                }
                return b + leftZeroFill(toInt(a / 60), 2) + leftZeroFill(toInt(a) % 60, 2);
            },
            z : function () {
                return this.zoneAbbr();
            },
            zz : function () {
                return this.zoneName();
            },
            X    : function () {
                return this.unix();
            },
            Q : function () {
                return this.quarter();
            }
        },

        deprecations = {},

        lists = ['months', 'monthsShort', 'weekdays', 'weekdaysShort', 'weekdaysMin'];

    // Pick the first defined of two or three arguments. dfl comes from
    // default.
    function dfl(a, b, c) {
        switch (arguments.length) {
            case 2: return a != null ? a : b;
            case 3: return a != null ? a : b != null ? b : c;
            default: throw new Error('Implement me');
        }
    }

    function defaultParsingFlags() {
        // We need to deep clone this object, and es5 standard is not very
        // helpful.
        return {
            empty : false,
            unusedTokens : [],
            unusedInput : [],
            overflow : -2,
            charsLeftOver : 0,
            nullInput : false,
            invalidMonth : null,
            invalidFormat : false,
            userInvalidated : false,
            iso: false
        };
    }

    function printMsg(msg) {
        if (moment.suppressDeprecationWarnings === false &&
                typeof console !== 'undefined' && console.warn) {
            console.warn("Deprecation warning: " + msg);
        }
    }

    function deprecate(msg, fn) {
        var firstTime = true;
        return extend(function () {
            if (firstTime) {
                printMsg(msg);
                firstTime = false;
            }
            return fn.apply(this, arguments);
        }, fn);
    }

    function deprecateSimple(name, msg) {
        if (!deprecations[name]) {
            printMsg(msg);
            deprecations[name] = true;
        }
    }

    function padToken(func, count) {
        return function (a) {
            return leftZeroFill(func.call(this, a), count);
        };
    }
    function ordinalizeToken(func, period) {
        return function (a) {
            return this.localeData().ordinal(func.call(this, a), period);
        };
    }

    while (ordinalizeTokens.length) {
        i = ordinalizeTokens.pop();
        formatTokenFunctions[i + 'o'] = ordinalizeToken(formatTokenFunctions[i], i);
    }
    while (paddedTokens.length) {
        i = paddedTokens.pop();
        formatTokenFunctions[i + i] = padToken(formatTokenFunctions[i], 2);
    }
    formatTokenFunctions.DDDD = padToken(formatTokenFunctions.DDD, 3);


    /************************************
        Constructors
    ************************************/

    function Locale() {
    }

    // Moment prototype object
    function Moment(config, skipOverflow) {
        if (skipOverflow !== false) {
            checkOverflow(config);
        }
        copyConfig(this, config);
        this._d = new Date(+config._d);
    }

    // Duration Constructor
    function Duration(duration) {
        var normalizedInput = normalizeObjectUnits(duration),
            years = normalizedInput.year || 0,
            quarters = normalizedInput.quarter || 0,
            months = normalizedInput.month || 0,
            weeks = normalizedInput.week || 0,
            days = normalizedInput.day || 0,
            hours = normalizedInput.hour || 0,
            minutes = normalizedInput.minute || 0,
            seconds = normalizedInput.second || 0,
            milliseconds = normalizedInput.millisecond || 0;

        // representation for dateAddRemove
        this._milliseconds = +milliseconds +
            seconds * 1e3 + // 1000
            minutes * 6e4 + // 1000 * 60
            hours * 36e5; // 1000 * 60 * 60
        // Because of dateAddRemove treats 24 hours as different from a
        // day when working around DST, we need to store them separately
        this._days = +days +
            weeks * 7;
        // It is impossible translate months into days without knowing
        // which months you are are talking about, so we have to store
        // it separately.
        this._months = +months +
            quarters * 3 +
            years * 12;

        this._data = {};

        this._locale = moment.localeData();

        this._bubble();
    }

    /************************************
        Helpers
    ************************************/


    function extend(a, b) {
        for (var i in b) {
            if (b.hasOwnProperty(i)) {
                a[i] = b[i];
            }
        }

        if (b.hasOwnProperty('toString')) {
            a.toString = b.toString;
        }

        if (b.hasOwnProperty('valueOf')) {
            a.valueOf = b.valueOf;
        }

        return a;
    }

    function copyConfig(to, from) {
        var i, prop, val;

        if (typeof from._isAMomentObject !== 'undefined') {
            to._isAMomentObject = from._isAMomentObject;
        }
        if (typeof from._i !== 'undefined') {
            to._i = from._i;
        }
        if (typeof from._f !== 'undefined') {
            to._f = from._f;
        }
        if (typeof from._l !== 'undefined') {
            to._l = from._l;
        }
        if (typeof from._strict !== 'undefined') {
            to._strict = from._strict;
        }
        if (typeof from._tzm !== 'undefined') {
            to._tzm = from._tzm;
        }
        if (typeof from._isUTC !== 'undefined') {
            to._isUTC = from._isUTC;
        }
        if (typeof from._offset !== 'undefined') {
            to._offset = from._offset;
        }
        if (typeof from._pf !== 'undefined') {
            to._pf = from._pf;
        }
        if (typeof from._locale !== 'undefined') {
            to._locale = from._locale;
        }

        if (momentProperties.length > 0) {
            for (i in momentProperties) {
                prop = momentProperties[i];
                val = from[prop];
                if (typeof val !== 'undefined') {
                    to[prop] = val;
                }
            }
        }

        return to;
    }

    function absRound(number) {
        if (number < 0) {
            return Math.ceil(number);
        } else {
            return Math.floor(number);
        }
    }

    // left zero fill a number
    // see http://jsperf.com/left-zero-filling for performance comparison
    function leftZeroFill(number, targetLength, forceSign) {
        var output = '' + Math.abs(number),
            sign = number >= 0;

        while (output.length < targetLength) {
            output = '0' + output;
        }
        return (sign ? (forceSign ? '+' : '') : '-') + output;
    }

    function positiveMomentsDifference(base, other) {
        var res = {milliseconds: 0, months: 0};

        res.months = other.month() - base.month() +
            (other.year() - base.year()) * 12;
        if (base.clone().add(res.months, 'M').isAfter(other)) {
            --res.months;
        }

        res.milliseconds = +other - +(base.clone().add(res.months, 'M'));

        return res;
    }

    function momentsDifference(base, other) {
        var res;
        other = makeAs(other, base);
        if (base.isBefore(other)) {
            res = positiveMomentsDifference(base, other);
        } else {
            res = positiveMomentsDifference(other, base);
            res.milliseconds = -res.milliseconds;
            res.months = -res.months;
        }

        return res;
    }

    // TODO: remove 'name' arg after deprecation is removed
    function createAdder(direction, name) {
        return function (val, period) {
            var dur, tmp;
            //invert the arguments, but complain about it
            if (period !== null && !isNaN(+period)) {
                deprecateSimple(name, "moment()." + name  + "(period, number) is deprecated. Please use moment()." + name + "(number, period).");
                tmp = val; val = period; period = tmp;
            }

            val = typeof val === 'string' ? +val : val;
            dur = moment.duration(val, period);
            addOrSubtractDurationFromMoment(this, dur, direction);
            return this;
        };
    }

    function addOrSubtractDurationFromMoment(mom, duration, isAdding, updateOffset) {
        var milliseconds = duration._milliseconds,
            days = duration._days,
            months = duration._months;
        updateOffset = updateOffset == null ? true : updateOffset;

        if (milliseconds) {
            mom._d.setTime(+mom._d + milliseconds * isAdding);
        }
        if (days) {
            rawSetter(mom, 'Date', rawGetter(mom, 'Date') + days * isAdding);
        }
        if (months) {
            rawMonthSetter(mom, rawGetter(mom, 'Month') + months * isAdding);
        }
        if (updateOffset) {
            moment.updateOffset(mom, days || months);
        }
    }

    // check if is an array
    function isArray(input) {
        return Object.prototype.toString.call(input) === '[object Array]';
    }

    function isDate(input) {
        return Object.prototype.toString.call(input) === '[object Date]' ||
            input instanceof Date;
    }

    // compare two arrays, return the number of differences
    function compareArrays(array1, array2, dontConvert) {
        var len = Math.min(array1.length, array2.length),
            lengthDiff = Math.abs(array1.length - array2.length),
            diffs = 0,
            i;
        for (i = 0; i < len; i++) {
            if ((dontConvert && array1[i] !== array2[i]) ||
                (!dontConvert && toInt(array1[i]) !== toInt(array2[i]))) {
                diffs++;
            }
        }
        return diffs + lengthDiff;
    }

    function normalizeUnits(units) {
        if (units) {
            var lowered = units.toLowerCase().replace(/(.)s$/, '$1');
            units = unitAliases[units] || camelFunctions[lowered] || lowered;
        }
        return units;
    }

    function normalizeObjectUnits(inputObject) {
        var normalizedInput = {},
            normalizedProp,
            prop;

        for (prop in inputObject) {
            if (inputObject.hasOwnProperty(prop)) {
                normalizedProp = normalizeUnits(prop);
                if (normalizedProp) {
                    normalizedInput[normalizedProp] = inputObject[prop];
                }
            }
        }

        return normalizedInput;
    }

    function makeList(field) {
        var count, setter;

        if (field.indexOf('week') === 0) {
            count = 7;
            setter = 'day';
        }
        else if (field.indexOf('month') === 0) {
            count = 12;
            setter = 'month';
        }
        else {
            return;
        }

        moment[field] = function (format, index) {
            var i, getter,
                method = moment._locale[field],
                results = [];

            if (typeof format === 'number') {
                index = format;
                format = undefined;
            }

            getter = function (i) {
                var m = moment().utc().set(setter, i);
                return method.call(moment._locale, m, format || '');
            };

            if (index != null) {
                return getter(index);
            }
            else {
                for (i = 0; i < count; i++) {
                    results.push(getter(i));
                }
                return results;
            }
        };
    }

    function toInt(argumentForCoercion) {
        var coercedNumber = +argumentForCoercion,
            value = 0;

        if (coercedNumber !== 0 && isFinite(coercedNumber)) {
            if (coercedNumber >= 0) {
                value = Math.floor(coercedNumber);
            } else {
                value = Math.ceil(coercedNumber);
            }
        }

        return value;
    }

    function daysInMonth(year, month) {
        return new Date(Date.UTC(year, month + 1, 0)).getUTCDate();
    }

    function weeksInYear(year, dow, doy) {
        return weekOfYear(moment([year, 11, 31 + dow - doy]), dow, doy).week;
    }

    function daysInYear(year) {
        return isLeapYear(year) ? 366 : 365;
    }

    function isLeapYear(year) {
        return (year % 4 === 0 && year % 100 !== 0) || year % 400 === 0;
    }

    function checkOverflow(m) {
        var overflow;
        if (m._a && m._pf.overflow === -2) {
            overflow =
                m._a[MONTH] < 0 || m._a[MONTH] > 11 ? MONTH :
                m._a[DATE] < 1 || m._a[DATE] > daysInMonth(m._a[YEAR], m._a[MONTH]) ? DATE :
                m._a[HOUR] < 0 || m._a[HOUR] > 23 ? HOUR :
                m._a[MINUTE] < 0 || m._a[MINUTE] > 59 ? MINUTE :
                m._a[SECOND] < 0 || m._a[SECOND] > 59 ? SECOND :
                m._a[MILLISECOND] < 0 || m._a[MILLISECOND] > 999 ? MILLISECOND :
                -1;

            if (m._pf._overflowDayOfYear && (overflow < YEAR || overflow > DATE)) {
                overflow = DATE;
            }

            m._pf.overflow = overflow;
        }
    }

    function isValid(m) {
        if (m._isValid == null) {
            m._isValid = !isNaN(m._d.getTime()) &&
                m._pf.overflow < 0 &&
                !m._pf.empty &&
                !m._pf.invalidMonth &&
                !m._pf.nullInput &&
                !m._pf.invalidFormat &&
                !m._pf.userInvalidated;

            if (m._strict) {
                m._isValid = m._isValid &&
                    m._pf.charsLeftOver === 0 &&
                    m._pf.unusedTokens.length === 0;
            }
        }
        return m._isValid;
    }

    function normalizeLocale(key) {
        return key ? key.toLowerCase().replace('_', '-') : key;
    }

    // pick the locale from the array
    // try ['en-au', 'en-gb'] as 'en-au', 'en-gb', 'en', as in move through the list trying each
    // substring from most specific to least, but move to the next array item if it's a more specific variant than the current root
    function chooseLocale(names) {
        var i = 0, j, next, locale, split;

        while (i < names.length) {
            split = normalizeLocale(names[i]).split('-');
            j = split.length;
            next = normalizeLocale(names[i + 1]);
            next = next ? next.split('-') : null;
            while (j > 0) {
                locale = loadLocale(split.slice(0, j).join('-'));
                if (locale) {
                    return locale;
                }
                if (next && next.length >= j && compareArrays(split, next, true) >= j - 1) {
                    //the next array item is better than a shallower substring of this one
                    break;
                }
                j--;
            }
            i++;
        }
        return null;
    }

    function loadLocale(name) {
        var oldLocale = null;
        if (!locales[name] && hasModule) {
            try {
                oldLocale = moment.locale();
                require('./locale/' + name);
                // because defineLocale currently also sets the global locale, we want to undo that for lazy loaded locales
                moment.locale(oldLocale);
            } catch (e) { }
        }
        return locales[name];
    }

    // Return a moment from input, that is local/utc/zone equivalent to model.
    function makeAs(input, model) {
        return model._isUTC ? moment(input).zone(model._offset || 0) :
            moment(input).local();
    }

    /************************************
        Locale
    ************************************/


    extend(Locale.prototype, {

        set : function (config) {
            var prop, i;
            for (i in config) {
                prop = config[i];
                if (typeof prop === 'function') {
                    this[i] = prop;
                } else {
                    this['_' + i] = prop;
                }
            }
        },

        _months : 'January_February_March_April_May_June_July_August_September_October_November_December'.split('_'),
        months : function (m) {
            return this._months[m.month()];
        },

        _monthsShort : 'Jan_Feb_Mar_Apr_May_Jun_Jul_Aug_Sep_Oct_Nov_Dec'.split('_'),
        monthsShort : function (m) {
            return this._monthsShort[m.month()];
        },

        monthsParse : function (monthName) {
            var i, mom, regex;

            if (!this._monthsParse) {
                this._monthsParse = [];
            }

            for (i = 0; i < 12; i++) {
                // make the regex if we don't have it already
                if (!this._monthsParse[i]) {
                    mom = moment.utc([2000, i]);
                    regex = '^' + this.months(mom, '') + '|^' + this.monthsShort(mom, '');
                    this._monthsParse[i] = new RegExp(regex.replace('.', ''), 'i');
                }
                // test the regex
                if (this._monthsParse[i].test(monthName)) {
                    return i;
                }
            }
        },

        _weekdays : 'Sunday_Monday_Tuesday_Wednesday_Thursday_Friday_Saturday'.split('_'),
        weekdays : function (m) {
            return this._weekdays[m.day()];
        },

        _weekdaysShort : 'Sun_Mon_Tue_Wed_Thu_Fri_Sat'.split('_'),
        weekdaysShort : function (m) {
            return this._weekdaysShort[m.day()];
        },

        _weekdaysMin : 'Su_Mo_Tu_We_Th_Fr_Sa'.split('_'),
        weekdaysMin : function (m) {
            return this._weekdaysMin[m.day()];
        },

        weekdaysParse : function (weekdayName) {
            var i, mom, regex;

            if (!this._weekdaysParse) {
                this._weekdaysParse = [];
            }

            for (i = 0; i < 7; i++) {
                // make the regex if we don't have it already
                if (!this._weekdaysParse[i]) {
                    mom = moment([2000, 1]).day(i);
                    regex = '^' + this.weekdays(mom, '') + '|^' + this.weekdaysShort(mom, '') + '|^' + this.weekdaysMin(mom, '');
                    this._weekdaysParse[i] = new RegExp(regex.replace('.', ''), 'i');
                }
                // test the regex
                if (this._weekdaysParse[i].test(weekdayName)) {
                    return i;
                }
            }
        },

        _longDateFormat : {
            LT : 'h:mm A',
            L : 'MM/DD/YYYY',
            LL : 'MMMM D, YYYY',
            LLL : 'MMMM D, YYYY LT',
            LLLL : 'dddd, MMMM D, YYYY LT'
        },
        longDateFormat : function (key) {
            var output = this._longDateFormat[key];
            if (!output && this._longDateFormat[key.toUpperCase()]) {
                output = this._longDateFormat[key.toUpperCase()].replace(/MMMM|MM|DD|dddd/g, function (val) {
                    return val.slice(1);
                });
                this._longDateFormat[key] = output;
            }
            return output;
        },

        isPM : function (input) {
            // IE8 Quirks Mode & IE7 Standards Mode do not allow accessing strings like arrays
            // Using charAt should be more compatible.
            return ((input + '').toLowerCase().charAt(0) === 'p');
        },

        _meridiemParse : /[ap]\.?m?\.?/i,
        meridiem : function (hours, minutes, isLower) {
            if (hours > 11) {
                return isLower ? 'pm' : 'PM';
            } else {
                return isLower ? 'am' : 'AM';
            }
        },

        _calendar : {
            sameDay : '[Today at] LT',
            nextDay : '[Tomorrow at] LT',
            nextWeek : 'dddd [at] LT',
            lastDay : '[Yesterday at] LT',
            lastWeek : '[Last] dddd [at] LT',
            sameElse : 'L'
        },
        calendar : function (key, mom) {
            var output = this._calendar[key];
            return typeof output === 'function' ? output.apply(mom) : output;
        },

        _relativeTime : {
            future : 'in %s',
            past : '%s ago',
            s : 'a few seconds',
            m : 'a minute',
            mm : '%d minutes',
            h : 'an hour',
            hh : '%d hours',
            d : 'a day',
            dd : '%d days',
            M : 'a month',
            MM : '%d months',
            y : 'a year',
            yy : '%d years'
        },

        relativeTime : function (number, withoutSuffix, string, isFuture) {
            var output = this._relativeTime[string];
            return (typeof output === 'function') ?
                output(number, withoutSuffix, string, isFuture) :
                output.replace(/%d/i, number);
        },

        pastFuture : function (diff, output) {
            var format = this._relativeTime[diff > 0 ? 'future' : 'past'];
            return typeof format === 'function' ? format(output) : format.replace(/%s/i, output);
        },

        ordinal : function (number) {
            return this._ordinal.replace('%d', number);
        },
        _ordinal : '%d',

        preparse : function (string) {
            return string;
        },

        postformat : function (string) {
            return string;
        },

        week : function (mom) {
            return weekOfYear(mom, this._week.dow, this._week.doy).week;
        },

        _week : {
            dow : 0, // Sunday is the first day of the week.
            doy : 6  // The week that contains Jan 1st is the first week of the year.
        },

        _invalidDate: 'Invalid date',
        invalidDate: function () {
            return this._invalidDate;
        }
    });

    /************************************
        Formatting
    ************************************/


    function removeFormattingTokens(input) {
        if (input.match(/\[[\s\S]/)) {
            return input.replace(/^\[|\]$/g, '');
        }
        return input.replace(/\\/g, '');
    }

    function makeFormatFunction(format) {
        var array = format.match(formattingTokens), i, length;

        for (i = 0, length = array.length; i < length; i++) {
            if (formatTokenFunctions[array[i]]) {
                array[i] = formatTokenFunctions[array[i]];
            } else {
                array[i] = removeFormattingTokens(array[i]);
            }
        }

        return function (mom) {
            var output = '';
            for (i = 0; i < length; i++) {
                output += array[i] instanceof Function ? array[i].call(mom, format) : array[i];
            }
            return output;
        };
    }

    // format date using native date object
    function formatMoment(m, format) {
        if (!m.isValid()) {
            return m.localeData().invalidDate();
        }

        format = expandFormat(format, m.localeData());

        if (!formatFunctions[format]) {
            formatFunctions[format] = makeFormatFunction(format);
        }

        return formatFunctions[format](m);
    }

    function expandFormat(format, locale) {
        var i = 5;

        function replaceLongDateFormatTokens(input) {
            return locale.longDateFormat(input) || input;
        }

        localFormattingTokens.lastIndex = 0;
        while (i >= 0 && localFormattingTokens.test(format)) {
            format = format.replace(localFormattingTokens, replaceLongDateFormatTokens);
            localFormattingTokens.lastIndex = 0;
            i -= 1;
        }

        return format;
    }


    /************************************
        Parsing
    ************************************/


    // get the regex to find the next token
    function getParseRegexForToken(token, config) {
        var a, strict = config._strict;
        switch (token) {
        case 'Q':
            return parseTokenOneDigit;
        case 'DDDD':
            return parseTokenThreeDigits;
        case 'YYYY':
        case 'GGGG':
        case 'gggg':
            return strict ? parseTokenFourDigits : parseTokenOneToFourDigits;
        case 'Y':
        case 'G':
        case 'g':
            return parseTokenSignedNumber;
        case 'YYYYYY':
        case 'YYYYY':
        case 'GGGGG':
        case 'ggggg':
            return strict ? parseTokenSixDigits : parseTokenOneToSixDigits;
        case 'S':
            if (strict) {
                return parseTokenOneDigit;
            }
            /* falls through */
        case 'SS':
            if (strict) {
                return parseTokenTwoDigits;
            }
            /* falls through */
        case 'SSS':
            if (strict) {
                return parseTokenThreeDigits;
            }
            /* falls through */
        case 'DDD':
            return parseTokenOneToThreeDigits;
        case 'MMM':
        case 'MMMM':
        case 'dd':
        case 'ddd':
        case 'dddd':
            return parseTokenWord;
        case 'a':
        case 'A':
            return config._locale._meridiemParse;
        case 'X':
            return parseTokenTimestampMs;
        case 'Z':
        case 'ZZ':
            return parseTokenTimezone;
        case 'T':
            return parseTokenT;
        case 'SSSS':
            return parseTokenDigits;
        case 'MM':
        case 'DD':
        case 'YY':
        case 'GG':
        case 'gg':
        case 'HH':
        case 'hh':
        case 'mm':
        case 'ss':
        case 'ww':
        case 'WW':
            return strict ? parseTokenTwoDigits : parseTokenOneOrTwoDigits;
        case 'M':
        case 'D':
        case 'd':
        case 'H':
        case 'h':
        case 'm':
        case 's':
        case 'w':
        case 'W':
        case 'e':
        case 'E':
            return parseTokenOneOrTwoDigits;
        case 'Do':
            return parseTokenOrdinal;
        default :
            a = new RegExp(regexpEscape(unescapeFormat(token.replace('\\', '')), 'i'));
            return a;
        }
    }

    function timezoneMinutesFromString(string) {
        string = string || '';
        var possibleTzMatches = (string.match(parseTokenTimezone) || []),
            tzChunk = possibleTzMatches[possibleTzMatches.length - 1] || [],
            parts = (tzChunk + '').match(parseTimezoneChunker) || ['-', 0, 0],
            minutes = +(parts[1] * 60) + toInt(parts[2]);

        return parts[0] === '+' ? -minutes : minutes;
    }

    // function to convert string input to date
    function addTimeToArrayFromToken(token, input, config) {
        var a, datePartArray = config._a;

        switch (token) {
        // QUARTER
        case 'Q':
            if (input != null) {
                datePartArray[MONTH] = (toInt(input) - 1) * 3;
            }
            break;
        // MONTH
        case 'M' : // fall through to MM
        case 'MM' :
            if (input != null) {
                datePartArray[MONTH] = toInt(input) - 1;
            }
            break;
        case 'MMM' : // fall through to MMMM
        case 'MMMM' :
            a = config._locale.monthsParse(input);
            // if we didn't find a month name, mark the date as invalid.
            if (a != null) {
                datePartArray[MONTH] = a;
            } else {
                config._pf.invalidMonth = input;
            }
            break;
        // DAY OF MONTH
        case 'D' : // fall through to DD
        case 'DD' :
            if (input != null) {
                datePartArray[DATE] = toInt(input);
            }
            break;
        case 'Do' :
            if (input != null) {
                datePartArray[DATE] = toInt(parseInt(input, 10));
            }
            break;
        // DAY OF YEAR
        case 'DDD' : // fall through to DDDD
        case 'DDDD' :
            if (input != null) {
                config._dayOfYear = toInt(input);
            }

            break;
        // YEAR
        case 'YY' :
            datePartArray[YEAR] = moment.parseTwoDigitYear(input);
            break;
        case 'YYYY' :
        case 'YYYYY' :
        case 'YYYYYY' :
            datePartArray[YEAR] = toInt(input);
            break;
        // AM / PM
        case 'a' : // fall through to A
        case 'A' :
            config._isPm = config._locale.isPM(input);
            break;
        // 24 HOUR
        case 'H' : // fall through to hh
        case 'HH' : // fall through to hh
        case 'h' : // fall through to hh
        case 'hh' :
            datePartArray[HOUR] = toInt(input);
            break;
        // MINUTE
        case 'm' : // fall through to mm
        case 'mm' :
            datePartArray[MINUTE] = toInt(input);
            break;
        // SECOND
        case 's' : // fall through to ss
        case 'ss' :
            datePartArray[SECOND] = toInt(input);
            break;
        // MILLISECOND
        case 'S' :
        case 'SS' :
        case 'SSS' :
        case 'SSSS' :
            datePartArray[MILLISECOND] = toInt(('0.' + input) * 1000);
            break;
        // UNIX TIMESTAMP WITH MS
        case 'X':
            config._d = new Date(parseFloat(input) * 1000);
            break;
        // TIMEZONE
        case 'Z' : // fall through to ZZ
        case 'ZZ' :
            config._useUTC = true;
            config._tzm = timezoneMinutesFromString(input);
            break;
        // WEEKDAY - human
        case 'dd':
        case 'ddd':
        case 'dddd':
            a = config._locale.weekdaysParse(input);
            // if we didn't get a weekday name, mark the date as invalid
            if (a != null) {
                config._w = config._w || {};
                config._w['d'] = a;
            } else {
                config._pf.invalidWeekday = input;
            }
            break;
        // WEEK, WEEK DAY - numeric
        case 'w':
        case 'ww':
        case 'W':
        case 'WW':
        case 'd':
        case 'e':
        case 'E':
            token = token.substr(0, 1);
            /* falls through */
        case 'gggg':
        case 'GGGG':
        case 'GGGGG':
            token = token.substr(0, 2);
            if (input) {
                config._w = config._w || {};
                config._w[token] = toInt(input);
            }
            break;
        case 'gg':
        case 'GG':
            config._w = config._w || {};
            config._w[token] = moment.parseTwoDigitYear(input);
        }
    }

    function dayOfYearFromWeekInfo(config) {
        var w, weekYear, week, weekday, dow, doy, temp;

        w = config._w;
        if (w.GG != null || w.W != null || w.E != null) {
            dow = 1;
            doy = 4;

            // TODO: We need to take the current isoWeekYear, but that depends on
            // how we interpret now (local, utc, fixed offset). So create
            // a now version of current config (take local/utc/offset flags, and
            // create now).
            weekYear = dfl(w.GG, config._a[YEAR], weekOfYear(moment(), 1, 4).year);
            week = dfl(w.W, 1);
            weekday = dfl(w.E, 1);
        } else {
            dow = config._locale._week.dow;
            doy = config._locale._week.doy;

            weekYear = dfl(w.gg, config._a[YEAR], weekOfYear(moment(), dow, doy).year);
            week = dfl(w.w, 1);

            if (w.d != null) {
                // weekday -- low day numbers are considered next week
                weekday = w.d;
                if (weekday < dow) {
                    ++week;
                }
            } else if (w.e != null) {
                // local weekday -- counting starts from begining of week
                weekday = w.e + dow;
            } else {
                // default to begining of week
                weekday = dow;
            }
        }
        temp = dayOfYearFromWeeks(weekYear, week, weekday, doy, dow);

        config._a[YEAR] = temp.year;
        config._dayOfYear = temp.dayOfYear;
    }

    // convert an array to a date.
    // the array should mirror the parameters below
    // note: all values past the year are optional and will default to the lowest possible value.
    // [year, month, day , hour, minute, second, millisecond]
    function dateFromConfig(config) {
        var i, date, input = [], currentDate, yearToUse;

        if (config._d) {
            return;
        }

        currentDate = currentDateArray(config);

        //compute day of the year from weeks and weekdays
        if (config._w && config._a[DATE] == null && config._a[MONTH] == null) {
            dayOfYearFromWeekInfo(config);
        }

        //if the day of the year is set, figure out what it is
        if (config._dayOfYear) {
            yearToUse = dfl(config._a[YEAR], currentDate[YEAR]);

            if (config._dayOfYear > daysInYear(yearToUse)) {
                config._pf._overflowDayOfYear = true;
            }

            date = makeUTCDate(yearToUse, 0, config._dayOfYear);
            config._a[MONTH] = date.getUTCMonth();
            config._a[DATE] = date.getUTCDate();
        }

        // Default to current date.
        // * if no year, month, day of month are given, default to today
        // * if day of month is given, default month and year
        // * if month is given, default only year
        // * if year is given, don't default anything
        for (i = 0; i < 3 && config._a[i] == null; ++i) {
            config._a[i] = input[i] = currentDate[i];
        }

        // Zero out whatever was not defaulted, including time
        for (; i < 7; i++) {
            config._a[i] = input[i] = (config._a[i] == null) ? (i === 2 ? 1 : 0) : config._a[i];
        }

        config._d = (config._useUTC ? makeUTCDate : makeDate).apply(null, input);
        // Apply timezone offset from input. The actual zone can be changed
        // with parseZone.
        if (config._tzm != null) {
            config._d.setUTCMinutes(config._d.getUTCMinutes() + config._tzm);
        }
    }

    function dateFromObject(config) {
        var normalizedInput;

        if (config._d) {
            return;
        }

        normalizedInput = normalizeObjectUnits(config._i);
        config._a = [
            normalizedInput.year,
            normalizedInput.month,
            normalizedInput.day,
            normalizedInput.hour,
            normalizedInput.minute,
            normalizedInput.second,
            normalizedInput.millisecond
        ];

        dateFromConfig(config);
    }

    function currentDateArray(config) {
        var now = new Date();
        if (config._useUTC) {
            return [
                now.getUTCFullYear(),
                now.getUTCMonth(),
                now.getUTCDate()
            ];
        } else {
            return [now.getFullYear(), now.getMonth(), now.getDate()];
        }
    }

    // date from string and format string
    function makeDateFromStringAndFormat(config) {
        if (config._f === moment.ISO_8601) {
            parseISO(config);
            return;
        }

        config._a = [];
        config._pf.empty = true;

        // This array is used to make a Date, either with `new Date` or `Date.UTC`
        var string = '' + config._i,
            i, parsedInput, tokens, token, skipped,
            stringLength = string.length,
            totalParsedInputLength = 0;

        tokens = expandFormat(config._f, config._locale).match(formattingTokens) || [];

        for (i = 0; i < tokens.length; i++) {
            token = tokens[i];
            parsedInput = (string.match(getParseRegexForToken(token, config)) || [])[0];
            if (parsedInput) {
                skipped = string.substr(0, string.indexOf(parsedInput));
                if (skipped.length > 0) {
                    config._pf.unusedInput.push(skipped);
                }
                string = string.slice(string.indexOf(parsedInput) + parsedInput.length);
                totalParsedInputLength += parsedInput.length;
            }
            // don't parse if it's not a known token
            if (formatTokenFunctions[token]) {
                if (parsedInput) {
                    config._pf.empty = false;
                }
                else {
                    config._pf.unusedTokens.push(token);
                }
                addTimeToArrayFromToken(token, parsedInput, config);
            }
            else if (config._strict && !parsedInput) {
                config._pf.unusedTokens.push(token);
            }
        }

        // add remaining unparsed input length to the string
        config._pf.charsLeftOver = stringLength - totalParsedInputLength;
        if (string.length > 0) {
            config._pf.unusedInput.push(string);
        }

        // handle am pm
        if (config._isPm && config._a[HOUR] < 12) {
            config._a[HOUR] += 12;
        }
        // if is 12 am, change hours to 0
        if (config._isPm === false && config._a[HOUR] === 12) {
            config._a[HOUR] = 0;
        }

        dateFromConfig(config);
        checkOverflow(config);
    }

    function unescapeFormat(s) {
        return s.replace(/\\(\[)|\\(\])|\[([^\]\[]*)\]|\\(.)/g, function (matched, p1, p2, p3, p4) {
            return p1 || p2 || p3 || p4;
        });
    }

    // Code from http://stackoverflow.com/questions/3561493/is-there-a-regexp-escape-function-in-javascript
    function regexpEscape(s) {
        return s.replace(/[-\/\\^$*+?.()|[\]{}]/g, '\\$&');
    }

    // date from string and array of format strings
    function makeDateFromStringAndArray(config) {
        var tempConfig,
            bestMoment,

            scoreToBeat,
            i,
            currentScore;

        if (config._f.length === 0) {
            config._pf.invalidFormat = true;
            config._d = new Date(NaN);
            return;
        }

        for (i = 0; i < config._f.length; i++) {
            currentScore = 0;
            tempConfig = copyConfig({}, config);
            tempConfig._pf = defaultParsingFlags();
            tempConfig._f = config._f[i];
            makeDateFromStringAndFormat(tempConfig);

            if (!isValid(tempConfig)) {
                continue;
            }

            // if there is any input that was not parsed add a penalty for that format
            currentScore += tempConfig._pf.charsLeftOver;

            //or tokens
            currentScore += tempConfig._pf.unusedTokens.length * 10;

            tempConfig._pf.score = currentScore;

            if (scoreToBeat == null || currentScore < scoreToBeat) {
                scoreToBeat = currentScore;
                bestMoment = tempConfig;
            }
        }

        extend(config, bestMoment || tempConfig);
    }

    // date from iso format
    function parseISO(config) {
        var i, l,
            string = config._i,
            match = isoRegex.exec(string);

        if (match) {
            config._pf.iso = true;
            for (i = 0, l = isoDates.length; i < l; i++) {
                if (isoDates[i][1].exec(string)) {
                    // match[5] should be "T" or undefined
                    config._f = isoDates[i][0] + (match[6] || ' ');
                    break;
                }
            }
            for (i = 0, l = isoTimes.length; i < l; i++) {
                if (isoTimes[i][1].exec(string)) {
                    config._f += isoTimes[i][0];
                    break;
                }
            }
            if (string.match(parseTokenTimezone)) {
                config._f += 'Z';
            }
            makeDateFromStringAndFormat(config);
        } else {
            config._isValid = false;
        }
    }

    // date from iso format or fallback
    function makeDateFromString(config) {
        parseISO(config);
        if (config._isValid === false) {
            delete config._isValid;
            moment.createFromInputFallback(config);
        }
    }

    function makeDateFromInput(config) {
        var input = config._i, matched;
        if (input === undefined) {
            config._d = new Date();
        } else if (isDate(input)) {
            config._d = new Date(+input);
        } else if ((matched = aspNetJsonRegex.exec(input)) !== null) {
            config._d = new Date(+matched[1]);
        } else if (typeof input === 'string') {
            makeDateFromString(config);
        } else if (isArray(input)) {
            config._a = input.slice(0);
            dateFromConfig(config);
        } else if (typeof(input) === 'object') {
            dateFromObject(config);
        } else if (typeof(input) === 'number') {
            // from milliseconds
            config._d = new Date(input);
        } else {
            moment.createFromInputFallback(config);
        }
    }

    function makeDate(y, m, d, h, M, s, ms) {
        //can't just apply() to create a date:
        //http://stackoverflow.com/questions/181348/instantiating-a-javascript-object-by-calling-prototype-constructor-apply
        var date = new Date(y, m, d, h, M, s, ms);

        //the date constructor doesn't accept years < 1970
        if (y < 1970) {
            date.setFullYear(y);
        }
        return date;
    }

    function makeUTCDate(y) {
        var date = new Date(Date.UTC.apply(null, arguments));
        if (y < 1970) {
            date.setUTCFullYear(y);
        }
        return date;
    }

    function parseWeekday(input, locale) {
        if (typeof input === 'string') {
            if (!isNaN(input)) {
                input = parseInt(input, 10);
            }
            else {
                input = locale.weekdaysParse(input);
                if (typeof input !== 'number') {
                    return null;
                }
            }
        }
        return input;
    }

    /************************************
        Relative Time
    ************************************/


    // helper function for moment.fn.from, moment.fn.fromNow, and moment.duration.fn.humanize
    function substituteTimeAgo(string, number, withoutSuffix, isFuture, locale) {
        return locale.relativeTime(number || 1, !!withoutSuffix, string, isFuture);
    }

    function relativeTime(posNegDuration, withoutSuffix, locale) {
        var duration = moment.duration(posNegDuration).abs(),
            seconds = round(duration.as('s')),
            minutes = round(duration.as('m')),
            hours = round(duration.as('h')),
            days = round(duration.as('d')),
            months = round(duration.as('M')),
            years = round(duration.as('y')),

            args = seconds < relativeTimeThresholds.s && ['s', seconds] ||
                minutes === 1 && ['m'] ||
                minutes < relativeTimeThresholds.m && ['mm', minutes] ||
                hours === 1 && ['h'] ||
                hours < relativeTimeThresholds.h && ['hh', hours] ||
                days === 1 && ['d'] ||
                days < relativeTimeThresholds.d && ['dd', days] ||
                months === 1 && ['M'] ||
                months < relativeTimeThresholds.M && ['MM', months] ||
                years === 1 && ['y'] || ['yy', years];

        args[2] = withoutSuffix;
        args[3] = +posNegDuration > 0;
        args[4] = locale;
        return substituteTimeAgo.apply({}, args);
    }


    /************************************
        Week of Year
    ************************************/


    // firstDayOfWeek       0 = sun, 6 = sat
    //                      the day of the week that starts the week
    //                      (usually sunday or monday)
    // firstDayOfWeekOfYear 0 = sun, 6 = sat
    //                      the first week is the week that contains the first
    //                      of this day of the week
    //                      (eg. ISO weeks use thursday (4))
    function weekOfYear(mom, firstDayOfWeek, firstDayOfWeekOfYear) {
        var end = firstDayOfWeekOfYear - firstDayOfWeek,
            daysToDayOfWeek = firstDayOfWeekOfYear - mom.day(),
            adjustedMoment;


        if (daysToDayOfWeek > end) {
            daysToDayOfWeek -= 7;
        }

        if (daysToDayOfWeek < end - 7) {
            daysToDayOfWeek += 7;
        }

        adjustedMoment = moment(mom).add(daysToDayOfWeek, 'd');
        return {
            week: Math.ceil(adjustedMoment.dayOfYear() / 7),
            year: adjustedMoment.year()
        };
    }

    //http://en.wikipedia.org/wiki/ISO_week_date#Calculating_a_date_given_the_year.2C_week_number_and_weekday
    function dayOfYearFromWeeks(year, week, weekday, firstDayOfWeekOfYear, firstDayOfWeek) {
        var d = makeUTCDate(year, 0, 1).getUTCDay(), daysToAdd, dayOfYear;

        d = d === 0 ? 7 : d;
        weekday = weekday != null ? weekday : firstDayOfWeek;
        daysToAdd = firstDayOfWeek - d + (d > firstDayOfWeekOfYear ? 7 : 0) - (d < firstDayOfWeek ? 7 : 0);
        dayOfYear = 7 * (week - 1) + (weekday - firstDayOfWeek) + daysToAdd + 1;

        return {
            year: dayOfYear > 0 ? year : year - 1,
            dayOfYear: dayOfYear > 0 ?  dayOfYear : daysInYear(year - 1) + dayOfYear
        };
    }

    /************************************
        Top Level Functions
    ************************************/

    function makeMoment(config) {
        var input = config._i,
            format = config._f;

        config._locale = config._locale || moment.localeData(config._l);

        if (input === null || (format === undefined && input === '')) {
            return moment.invalid({nullInput: true});
        }

        if (typeof input === 'string') {
            config._i = input = config._locale.preparse(input);
        }

        if (moment.isMoment(input)) {
            return new Moment(input, true);
        } else if (format) {
            if (isArray(format)) {
                makeDateFromStringAndArray(config);
            } else {
                makeDateFromStringAndFormat(config);
            }
        } else {
            makeDateFromInput(config);
        }

        return new Moment(config);
    }

    moment = function (input, format, locale, strict) {
        var c;

        if (typeof(locale) === "boolean") {
            strict = locale;
            locale = undefined;
        }
        // object construction must be done this way.
        // https://github.com/moment/moment/issues/1423
        c = {};
        c._isAMomentObject = true;
        c._i = input;
        c._f = format;
        c._l = locale;
        c._strict = strict;
        c._isUTC = false;
        c._pf = defaultParsingFlags();

        return makeMoment(c);
    };

    moment.suppressDeprecationWarnings = false;

    moment.createFromInputFallback = deprecate(
        'moment construction falls back to js Date. This is ' +
        'discouraged and will be removed in upcoming major ' +
        'release. Please refer to ' +
        'https://github.com/moment/moment/issues/1407 for more info.',
        function (config) {
            config._d = new Date(config._i);
        }
    );

    // Pick a moment m from moments so that m[fn](other) is true for all
    // other. This relies on the function fn to be transitive.
    //
    // moments should either be an array of moment objects or an array, whose
    // first element is an array of moment objects.
    function pickBy(fn, moments) {
        var res, i;
        if (moments.length === 1 && isArray(moments[0])) {
            moments = moments[0];
        }
        if (!moments.length) {
            return moment();
        }
        res = moments[0];
        for (i = 1; i < moments.length; ++i) {
            if (moments[i][fn](res)) {
                res = moments[i];
            }
        }
        return res;
    }

    moment.min = function () {
        var args = [].slice.call(arguments, 0);

        return pickBy('isBefore', args);
    };

    moment.max = function () {
        var args = [].slice.call(arguments, 0);

        return pickBy('isAfter', args);
    };

    // creating with utc
    moment.utc = function (input, format, locale, strict) {
        var c;

        if (typeof(locale) === "boolean") {
            strict = locale;
            locale = undefined;
        }
        // object construction must be done this way.
        // https://github.com/moment/moment/issues/1423
        c = {};
        c._isAMomentObject = true;
        c._useUTC = true;
        c._isUTC = true;
        c._l = locale;
        c._i = input;
        c._f = format;
        c._strict = strict;
        c._pf = defaultParsingFlags();

        return makeMoment(c).utc();
    };

    // creating with unix timestamp (in seconds)
    moment.unix = function (input) {
        return moment(input * 1000);
    };

    // duration
    moment.duration = function (input, key) {
        var duration = input,
            // matching against regexp is expensive, do it on demand
            match = null,
            sign,
            ret,
            parseIso,
            diffRes;

        if (moment.isDuration(input)) {
            duration = {
                ms: input._milliseconds,
                d: input._days,
                M: input._months
            };
        } else if (typeof input === 'number') {
            duration = {};
            if (key) {
                duration[key] = input;
            } else {
                duration.milliseconds = input;
            }
        } else if (!!(match = aspNetTimeSpanJsonRegex.exec(input))) {
            sign = (match[1] === '-') ? -1 : 1;
            duration = {
                y: 0,
                d: toInt(match[DATE]) * sign,
                h: toInt(match[HOUR]) * sign,
                m: toInt(match[MINUTE]) * sign,
                s: toInt(match[SECOND]) * sign,
                ms: toInt(match[MILLISECOND]) * sign
            };
        } else if (!!(match = isoDurationRegex.exec(input))) {
            sign = (match[1] === '-') ? -1 : 1;
            parseIso = function (inp) {
                // We'd normally use ~~inp for this, but unfortunately it also
                // converts floats to ints.
                // inp may be undefined, so careful calling replace on it.
                var res = inp && parseFloat(inp.replace(',', '.'));
                // apply sign while we're at it
                return (isNaN(res) ? 0 : res) * sign;
            };
            duration = {
                y: parseIso(match[2]),
                M: parseIso(match[3]),
                d: parseIso(match[4]),
                h: parseIso(match[5]),
                m: parseIso(match[6]),
                s: parseIso(match[7]),
                w: parseIso(match[8])
            };
        } else if (typeof duration === 'object' &&
                ('from' in duration || 'to' in duration)) {
            diffRes = momentsDifference(moment(duration.from), moment(duration.to));

            duration = {};
            duration.ms = diffRes.milliseconds;
            duration.M = diffRes.months;
        }

        ret = new Duration(duration);

        if (moment.isDuration(input) && input.hasOwnProperty('_locale')) {
            ret._locale = input._locale;
        }

        return ret;
    };

    // version number
    moment.version = VERSION;

    // default format
    moment.defaultFormat = isoFormat;

    // constant that refers to the ISO standard
    moment.ISO_8601 = function () {};

    // Plugins that add properties should also add the key here (null value),
    // so we can properly clone ourselves.
    moment.momentProperties = momentProperties;

    // This function will be called whenever a moment is mutated.
    // It is intended to keep the offset in sync with the timezone.
    moment.updateOffset = function () {};

    // This function allows you to set a threshold for relative time strings
    moment.relativeTimeThreshold = function (threshold, limit) {
        if (relativeTimeThresholds[threshold] === undefined) {
            return false;
        }
        if (limit === undefined) {
            return relativeTimeThresholds[threshold];
        }
        relativeTimeThresholds[threshold] = limit;
        return true;
    };

    moment.lang = deprecate(
        "moment.lang is deprecated. Use moment.locale instead.",
        function (key, value) {
            return moment.locale(key, value);
        }
    );

    // This function will load locale and then set the global locale.  If
    // no arguments are passed in, it will simply return the current global
    // locale key.
    moment.locale = function (key, values) {
        var data;
        if (key) {
            if (typeof(values) !== "undefined") {
                data = moment.defineLocale(key, values);
            }
            else {
                data = moment.localeData(key);
            }

            if (data) {
                moment.duration._locale = moment._locale = data;
            }
        }

        return moment._locale._abbr;
    };

    moment.defineLocale = function (name, values) {
        if (values !== null) {
            values.abbr = name;
            if (!locales[name]) {
                locales[name] = new Locale();
            }
            locales[name].set(values);

            // backwards compat for now: also set the locale
            moment.locale(name);

            return locales[name];
        } else {
            // useful for testing
            delete locales[name];
            return null;
        }
    };

    moment.langData = deprecate(
        "moment.langData is deprecated. Use moment.localeData instead.",
        function (key) {
            return moment.localeData(key);
        }
    );

    // returns locale data
    moment.localeData = function (key) {
        var locale;

        if (key && key._locale && key._locale._abbr) {
            key = key._locale._abbr;
        }

        if (!key) {
            return moment._locale;
        }

        if (!isArray(key)) {
            //short-circuit everything else
            locale = loadLocale(key);
            if (locale) {
                return locale;
            }
            key = [key];
        }

        return chooseLocale(key);
    };

    // compare moment object
    moment.isMoment = function (obj) {
        return obj instanceof Moment ||
            (obj != null &&  obj.hasOwnProperty('_isAMomentObject'));
    };

    // for typechecking Duration objects
    moment.isDuration = function (obj) {
        return obj instanceof Duration;
    };

    for (i = lists.length - 1; i >= 0; --i) {
        makeList(lists[i]);
    }

    moment.normalizeUnits = function (units) {
        return normalizeUnits(units);
    };

    moment.invalid = function (flags) {
        var m = moment.utc(NaN);
        if (flags != null) {
            extend(m._pf, flags);
        }
        else {
            m._pf.userInvalidated = true;
        }

        return m;
    };

    moment.parseZone = function () {
        return moment.apply(null, arguments).parseZone();
    };

    moment.parseTwoDigitYear = function (input) {
        return toInt(input) + (toInt(input) > 68 ? 1900 : 2000);
    };

    /************************************
        Moment Prototype
    ************************************/


    extend(moment.fn = Moment.prototype, {

        clone : function () {
            return moment(this);
        },

        valueOf : function () {
            return +this._d + ((this._offset || 0) * 60000);
        },

        unix : function () {
            return Math.floor(+this / 1000);
        },

        toString : function () {
            return this.clone().locale('en').format("ddd MMM DD YYYY HH:mm:ss [GMT]ZZ");
        },

        toDate : function () {
            return this._offset ? new Date(+this) : this._d;
        },

        toISOString : function () {
            var m = moment(this).utc();
            if (0 < m.year() && m.year() <= 9999) {
                return formatMoment(m, 'YYYY-MM-DD[T]HH:mm:ss.SSS[Z]');
            } else {
                return formatMoment(m, 'YYYYYY-MM-DD[T]HH:mm:ss.SSS[Z]');
            }
        },

        toArray : function () {
            var m = this;
            return [
                m.year(),
                m.month(),
                m.date(),
                m.hours(),
                m.minutes(),
                m.seconds(),
                m.milliseconds()
            ];
        },

        isValid : function () {
            return isValid(this);
        },

        isDSTShifted : function () {
            if (this._a) {
                return this.isValid() && compareArrays(this._a, (this._isUTC ? moment.utc(this._a) : moment(this._a)).toArray()) > 0;
            }

            return false;
        },

        parsingFlags : function () {
            return extend({}, this._pf);
        },

        invalidAt: function () {
            return this._pf.overflow;
        },

        utc : function (keepLocalTime) {
            return this.zone(0, keepLocalTime);
        },

        local : function (keepLocalTime) {
            if (this._isUTC) {
                this.zone(0, keepLocalTime);
                this._isUTC = false;

                if (keepLocalTime) {
                    this.add(this._d.getTimezoneOffset(), 'm');
                }
            }
            return this;
        },

        format : function (inputString) {
            var output = formatMoment(this, inputString || moment.defaultFormat);
            return this.localeData().postformat(output);
        },

        add : createAdder(1, 'add'),

        subtract : createAdder(-1, 'subtract'),

        diff : function (input, units, asFloat) {
            var that = makeAs(input, this),
                zoneDiff = (this.zone() - that.zone()) * 6e4,
                diff, output;

            units = normalizeUnits(units);

            if (units === 'year' || units === 'month') {
                // average number of days in the months in the given dates
                diff = (this.daysInMonth() + that.daysInMonth()) * 432e5; // 24 * 60 * 60 * 1000 / 2
                // difference in months
                output = ((this.year() - that.year()) * 12) + (this.month() - that.month());
                // adjust by taking difference in days, average number of days
                // and dst in the given months.
                output += ((this - moment(this).startOf('month')) -
                        (that - moment(that).startOf('month'))) / diff;
                // same as above but with zones, to negate all dst
                output -= ((this.zone() - moment(this).startOf('month').zone()) -
                        (that.zone() - moment(that).startOf('month').zone())) * 6e4 / diff;
                if (units === 'year') {
                    output = output / 12;
                }
            } else {
                diff = (this - that);
                output = units === 'second' ? diff / 1e3 : // 1000
                    units === 'minute' ? diff / 6e4 : // 1000 * 60
                    units === 'hour' ? diff / 36e5 : // 1000 * 60 * 60
                    units === 'day' ? (diff - zoneDiff) / 864e5 : // 1000 * 60 * 60 * 24, negate dst
                    units === 'week' ? (diff - zoneDiff) / 6048e5 : // 1000 * 60 * 60 * 24 * 7, negate dst
                    diff;
            }
            return asFloat ? output : absRound(output);
        },

        from : function (time, withoutSuffix) {
            return moment.duration({to: this, from: time}).locale(this.locale()).humanize(!withoutSuffix);
        },

        fromNow : function (withoutSuffix) {
            return this.from(moment(), withoutSuffix);
        },

        calendar : function (time) {
            // We want to compare the start of today, vs this.
            // Getting start-of-today depends on whether we're zone'd or not.
            var now = time || moment(),
                sod = makeAs(now, this).startOf('day'),
                diff = this.diff(sod, 'days', true),
                format = diff < -6 ? 'sameElse' :
                    diff < -1 ? 'lastWeek' :
                    diff < 0 ? 'lastDay' :
                    diff < 1 ? 'sameDay' :
                    diff < 2 ? 'nextDay' :
                    diff < 7 ? 'nextWeek' : 'sameElse';
            return this.format(this.localeData().calendar(format, this));
        },

        isLeapYear : function () {
            return isLeapYear(this.year());
        },

        isDST : function () {
            return (this.zone() < this.clone().month(0).zone() ||
                this.zone() < this.clone().month(5).zone());
        },

        day : function (input) {
            var day = this._isUTC ? this._d.getUTCDay() : this._d.getDay();
            if (input != null) {
                input = parseWeekday(input, this.localeData());
                return this.add(input - day, 'd');
            } else {
                return day;
            }
        },

        month : makeAccessor('Month', true),

        startOf : function (units) {
            units = normalizeUnits(units);
            // the following switch intentionally omits break keywords
            // to utilize falling through the cases.
            switch (units) {
            case 'year':
                this.month(0);
                /* falls through */
            case 'quarter':
            case 'month':
                this.date(1);
                /* falls through */
            case 'week':
            case 'isoWeek':
            case 'day':
                this.hours(0);
                /* falls through */
            case 'hour':
                this.minutes(0);
                /* falls through */
            case 'minute':
                this.seconds(0);
                /* falls through */
            case 'second':
                this.milliseconds(0);
                /* falls through */
            }

            // weeks are a special case
            if (units === 'week') {
                this.weekday(0);
            } else if (units === 'isoWeek') {
                this.isoWeekday(1);
            }

            // quarters are also special
            if (units === 'quarter') {
                this.month(Math.floor(this.month() / 3) * 3);
            }

            return this;
        },

        endOf: function (units) {
            units = normalizeUnits(units);
            return this.startOf(units).add(1, (units === 'isoWeek' ? 'week' : units)).subtract(1, 'ms');
        },

        isAfter: function (input, units) {
            units = typeof units !== 'undefined' ? units : 'millisecond';
            return +this.clone().startOf(units) > +moment(input).startOf(units);
        },

        isBefore: function (input, units) {
            units = typeof units !== 'undefined' ? units : 'millisecond';
            return +this.clone().startOf(units) < +moment(input).startOf(units);
        },

        isSame: function (input, units) {
            units = units || 'ms';
            return +this.clone().startOf(units) === +makeAs(input, this).startOf(units);
        },

        min: deprecate(
                 'moment().min is deprecated, use moment.min instead. https://github.com/moment/moment/issues/1548',
                 function (other) {
                     other = moment.apply(null, arguments);
                     return other < this ? this : other;
                 }
         ),

        max: deprecate(
                'moment().max is deprecated, use moment.max instead. https://github.com/moment/moment/issues/1548',
                function (other) {
                    other = moment.apply(null, arguments);
                    return other > this ? this : other;
                }
        ),

        // keepLocalTime = true means only change the timezone, without
        // affecting the local hour. So 5:31:26 +0300 --[zone(2, true)]-->
        // 5:31:26 +0200 It is possible that 5:31:26 doesn't exist int zone
        // +0200, so we adjust the time as needed, to be valid.
        //
        // Keeping the time actually adds/subtracts (one hour)
        // from the actual represented time. That is why we call updateOffset
        // a second time. In case it wants us to change the offset again
        // _changeInProgress == true case, then we have to adjust, because
        // there is no such time in the given timezone.
        zone : function (input, keepLocalTime) {
            var offset = this._offset || 0,
                localAdjust;
            if (input != null) {
                if (typeof input === 'string') {
                    input = timezoneMinutesFromString(input);
                }
                if (Math.abs(input) < 16) {
                    input = input * 60;
                }
                if (!this._isUTC && keepLocalTime) {
                    localAdjust = this._d.getTimezoneOffset();
                }
                this._offset = input;
                this._isUTC = true;
                if (localAdjust != null) {
                    this.subtract(localAdjust, 'm');
                }
                if (offset !== input) {
                    if (!keepLocalTime || this._changeInProgress) {
                        addOrSubtractDurationFromMoment(this,
                                moment.duration(offset - input, 'm'), 1, false);
                    } else if (!this._changeInProgress) {
                        this._changeInProgress = true;
                        moment.updateOffset(this, true);
                        this._changeInProgress = null;
                    }
                }
            } else {
                return this._isUTC ? offset : this._d.getTimezoneOffset();
            }
            return this;
        },

        zoneAbbr : function () {
            return this._isUTC ? 'UTC' : '';
        },

        zoneName : function () {
            return this._isUTC ? 'Coordinated Universal Time' : '';
        },

        parseZone : function () {
            if (this._tzm) {
                this.zone(this._tzm);
            } else if (typeof this._i === 'string') {
                this.zone(this._i);
            }
            return this;
        },

        hasAlignedHourOffset : function (input) {
            if (!input) {
                input = 0;
            }
            else {
                input = moment(input).zone();
            }

            return (this.zone() - input) % 60 === 0;
        },

        daysInMonth : function () {
            return daysInMonth(this.year(), this.month());
        },

        dayOfYear : function (input) {
            var dayOfYear = round((moment(this).startOf('day') - moment(this).startOf('year')) / 864e5) + 1;
            return input == null ? dayOfYear : this.add((input - dayOfYear), 'd');
        },

        quarter : function (input) {
            return input == null ? Math.ceil((this.month() + 1) / 3) : this.month((input - 1) * 3 + this.month() % 3);
        },

        weekYear : function (input) {
            var year = weekOfYear(this, this.localeData()._week.dow, this.localeData()._week.doy).year;
            return input == null ? year : this.add((input - year), 'y');
        },

        isoWeekYear : function (input) {
            var year = weekOfYear(this, 1, 4).year;
            return input == null ? year : this.add((input - year), 'y');
        },

        week : function (input) {
            var week = this.localeData().week(this);
            return input == null ? week : this.add((input - week) * 7, 'd');
        },

        isoWeek : function (input) {
            var week = weekOfYear(this, 1, 4).week;
            return input == null ? week : this.add((input - week) * 7, 'd');
        },

        weekday : function (input) {
            var weekday = (this.day() + 7 - this.localeData()._week.dow) % 7;
            return input == null ? weekday : this.add(input - weekday, 'd');
        },

        isoWeekday : function (input) {
            // behaves the same as moment#day except
            // as a getter, returns 7 instead of 0 (1-7 range instead of 0-6)
            // as a setter, sunday should belong to the previous week.
            return input == null ? this.day() || 7 : this.day(this.day() % 7 ? input : input - 7);
        },

        isoWeeksInYear : function () {
            return weeksInYear(this.year(), 1, 4);
        },

        weeksInYear : function () {
            var weekInfo = this.localeData()._week;
            return weeksInYear(this.year(), weekInfo.dow, weekInfo.doy);
        },

        get : function (units) {
            units = normalizeUnits(units);
            return this[units]();
        },

        set : function (units, value) {
            units = normalizeUnits(units);
            if (typeof this[units] === 'function') {
                this[units](value);
            }
            return this;
        },

        // If passed a locale key, it will set the locale for this
        // instance.  Otherwise, it will return the locale configuration
        // variables for this instance.
        locale : function (key) {
            if (key === undefined) {
                return this._locale._abbr;
            } else {
                this._locale = moment.localeData(key);
                return this;
            }
        },

        lang : deprecate(
            "moment().lang() is deprecated. Use moment().localeData() instead.",
            function (key) {
                if (key === undefined) {
                    return this.localeData();
                } else {
                    this._locale = moment.localeData(key);
                    return this;
                }
            }
        ),

        localeData : function () {
            return this._locale;
        }
    });

    function rawMonthSetter(mom, value) {
        var dayOfMonth;

        // TODO: Move this out of here!
        if (typeof value === 'string') {
            value = mom.localeData().monthsParse(value);
            // TODO: Another silent failure?
            if (typeof value !== 'number') {
                return mom;
            }
        }

        dayOfMonth = Math.min(mom.date(),
                daysInMonth(mom.year(), value));
        mom._d['set' + (mom._isUTC ? 'UTC' : '') + 'Month'](value, dayOfMonth);
        return mom;
    }

    function rawGetter(mom, unit) {
        return mom._d['get' + (mom._isUTC ? 'UTC' : '') + unit]();
    }

    function rawSetter(mom, unit, value) {
        if (unit === 'Month') {
            return rawMonthSetter(mom, value);
        } else {
            return mom._d['set' + (mom._isUTC ? 'UTC' : '') + unit](value);
        }
    }

    function makeAccessor(unit, keepTime) {
        return function (value) {
            if (value != null) {
                rawSetter(this, unit, value);
                moment.updateOffset(this, keepTime);
                return this;
            } else {
                return rawGetter(this, unit);
            }
        };
    }

    moment.fn.millisecond = moment.fn.milliseconds = makeAccessor('Milliseconds', false);
    moment.fn.second = moment.fn.seconds = makeAccessor('Seconds', false);
    moment.fn.minute = moment.fn.minutes = makeAccessor('Minutes', false);
    // Setting the hour should keep the time, because the user explicitly
    // specified which hour he wants. So trying to maintain the same hour (in
    // a new timezone) makes sense. Adding/subtracting hours does not follow
    // this rule.
    moment.fn.hour = moment.fn.hours = makeAccessor('Hours', true);
    // moment.fn.month is defined separately
    moment.fn.date = makeAccessor('Date', true);
    moment.fn.dates = deprecate('dates accessor is deprecated. Use date instead.', makeAccessor('Date', true));
    moment.fn.year = makeAccessor('FullYear', true);
    moment.fn.years = deprecate('years accessor is deprecated. Use year instead.', makeAccessor('FullYear', true));

    // add plural methods
    moment.fn.days = moment.fn.day;
    moment.fn.months = moment.fn.month;
    moment.fn.weeks = moment.fn.week;
    moment.fn.isoWeeks = moment.fn.isoWeek;
    moment.fn.quarters = moment.fn.quarter;

    // add aliased format methods
    moment.fn.toJSON = moment.fn.toISOString;

    /************************************
        Duration Prototype
    ************************************/


    function daysToYears (days) {
        // 400 years have 146097 days (taking into account leap year rules)
        return days * 400 / 146097;
    }

    function yearsToDays (years) {
        // years * 365 + absRound(years / 4) -
        //     absRound(years / 100) + absRound(years / 400);
        return years * 146097 / 400;
    }

    extend(moment.duration.fn = Duration.prototype, {

        _bubble : function () {
            var milliseconds = this._milliseconds,
                days = this._days,
                months = this._months,
                data = this._data,
                seconds, minutes, hours, years = 0;

            // The following code bubbles up values, see the tests for
            // examples of what that means.
            data.milliseconds = milliseconds % 1000;

            seconds = absRound(milliseconds / 1000);
            data.seconds = seconds % 60;

            minutes = absRound(seconds / 60);
            data.minutes = minutes % 60;

            hours = absRound(minutes / 60);
            data.hours = hours % 24;

            days += absRound(hours / 24);

            // Accurately convert days to years, assume start from year 0.
            years = absRound(daysToYears(days));
            days -= absRound(yearsToDays(years));

            // 30 days to a month
            // TODO (iskren): Use anchor date (like 1st Jan) to compute this.
            months += absRound(days / 30);
            days %= 30;

            // 12 months -> 1 year
            years += absRound(months / 12);
            months %= 12;

            data.days = days;
            data.months = months;
            data.years = years;
        },

        abs : function () {
            this._milliseconds = Math.abs(this._milliseconds);
            this._days = Math.abs(this._days);
            this._months = Math.abs(this._months);

            this._data.milliseconds = Math.abs(this._data.milliseconds);
            this._data.seconds = Math.abs(this._data.seconds);
            this._data.minutes = Math.abs(this._data.minutes);
            this._data.hours = Math.abs(this._data.hours);
            this._data.months = Math.abs(this._data.months);
            this._data.years = Math.abs(this._data.years);

            return this;
        },

        weeks : function () {
            return absRound(this.days() / 7);
        },

        valueOf : function () {
            return this._milliseconds +
              this._days * 864e5 +
              (this._months % 12) * 2592e6 +
              toInt(this._months / 12) * 31536e6;
        },

        humanize : function (withSuffix) {
            var output = relativeTime(this, !withSuffix, this.localeData());

            if (withSuffix) {
                output = this.localeData().pastFuture(+this, output);
            }

            return this.localeData().postformat(output);
        },

        add : function (input, val) {
            // supports only 2.0-style add(1, 's') or add(moment)
            var dur = moment.duration(input, val);

            this._milliseconds += dur._milliseconds;
            this._days += dur._days;
            this._months += dur._months;

            this._bubble();

            return this;
        },

        subtract : function (input, val) {
            var dur = moment.duration(input, val);

            this._milliseconds -= dur._milliseconds;
            this._days -= dur._days;
            this._months -= dur._months;

            this._bubble();

            return this;
        },

        get : function (units) {
            units = normalizeUnits(units);
            return this[units.toLowerCase() + 's']();
        },

        as : function (units) {
            var days, months;
            units = normalizeUnits(units);

            days = this._days + this._milliseconds / 864e5;
            if (units === 'month' || units === 'year') {
                months = this._months + daysToYears(days) * 12;
                return units === 'month' ? months : months / 12;
            } else {
                days += yearsToDays(this._months / 12);
                switch (units) {
                    case 'week': return days / 7;
                    case 'day': return days;
                    case 'hour': return days * 24;
                    case 'minute': return days * 24 * 60;
                    case 'second': return days * 24 * 60 * 60;
                    case 'millisecond': return days * 24 * 60 * 60 * 1000;
                    default: throw new Error('Unknown unit ' + units);
                }
            }
        },

        lang : moment.fn.lang,
        locale : moment.fn.locale,

        toIsoString : deprecate(
            "toIsoString() is deprecated. Please use toISOString() instead " +
            "(notice the capitals)",
            function () {
                return this.toISOString();
            }
        ),

        toISOString : function () {
            // inspired by https://github.com/dordille/moment-isoduration/blob/master/moment.isoduration.js
            var years = Math.abs(this.years()),
                months = Math.abs(this.months()),
                days = Math.abs(this.days()),
                hours = Math.abs(this.hours()),
                minutes = Math.abs(this.minutes()),
                seconds = Math.abs(this.seconds() + this.milliseconds() / 1000);

            if (!this.asSeconds()) {
                // this is the same as C#'s (Noda) and python (isodate)...
                // but not other JS (goog.date)
                return 'P0D';
            }

            return (this.asSeconds() < 0 ? '-' : '') +
                'P' +
                (years ? years + 'Y' : '') +
                (months ? months + 'M' : '') +
                (days ? days + 'D' : '') +
                ((hours || minutes || seconds) ? 'T' : '') +
                (hours ? hours + 'H' : '') +
                (minutes ? minutes + 'M' : '') +
                (seconds ? seconds + 'S' : '');
        },

        localeData : function () {
            return this._locale;
        }
    });

    function makeDurationGetter(name) {
        moment.duration.fn[name] = function () {
            return this._data[name];
        };
    }

    for (i in unitMillisecondFactors) {
        if (unitMillisecondFactors.hasOwnProperty(i)) {
            makeDurationGetter(i.toLowerCase());
        }
    }

    moment.duration.fn.asMilliseconds = function () {
        return this.as('ms');
    };
    moment.duration.fn.asSeconds = function () {
        return this.as('s');
    };
    moment.duration.fn.asMinutes = function () {
        return this.as('m');
    };
    moment.duration.fn.asHours = function () {
        return this.as('h');
    };
    moment.duration.fn.asDays = function () {
        return this.as('d');
    };
    moment.duration.fn.asWeeks = function () {
        return this.as('weeks');
    };
    moment.duration.fn.asMonths = function () {
        return this.as('M');
    };
    moment.duration.fn.asYears = function () {
        return this.as('y');
    };

    /************************************
        Default Locale
    ************************************/


    // Set default locale, other locale will inherit from English.
    moment.locale('en', {
        ordinal : function (number) {
            var b = number % 10,
                output = (toInt(number % 100 / 10) === 1) ? 'th' :
                (b === 1) ? 'st' :
                (b === 2) ? 'nd' :
                (b === 3) ? 'rd' : 'th';
            return number + output;
        }
    });

    /* EMBED_LOCALES */

    /************************************
        Exposing Moment
    ************************************/

    function makeGlobal(shouldDeprecate) {
        /*global ender:false */
        if (typeof ender !== 'undefined') {
            return;
        }
        oldGlobalMoment = globalScope.moment;
        if (shouldDeprecate) {
            globalScope.moment = deprecate(
                    'Accessing Moment through the global scope is ' +
                    'deprecated, and will be removed in an upcoming ' +
                    'release.',
                    moment);
        } else {
            globalScope.moment = moment;
        }
    }

    // CommonJS module is defined
    if (hasModule) {
        module.exports = moment;
    } else if (typeof define === 'function' && define.amd) {
        define('moment', function (require, exports, module) {
            if (module.config && module.config() && module.config().noGlobal === true) {
                // release the global variable
                globalScope.moment = oldGlobalMoment;
            }

            return moment;
        });
        makeGlobal(true);
    } else {
        makeGlobal();
    }
}).call(this);

(function(root, factory) {
    if(typeof exports === 'object') {
        module.exports = factory(require('moment'));
    }
    else if(typeof define === 'function' && define.amd) {
        define('moment-range', ['moment'], factory);
    }
    else {
        root.moment = factory(root.moment);
    }
}(this, function(moment) {
var DateRange, INTERVALS;

INTERVALS = {
  year: true,
  month: true,
  week: true,
  day: true,
  hour: true,
  minute: true,
  second: true
};

/**
  * DateRange class to store ranges and query dates.
  * @typedef {!Object}
*
*/


DateRange = (function() {
  /**
    * DateRange instance.
    * @param {(Moment|Date)} start Start of interval.
    * @param {(Moment|Date)} end   End of interval.
    * @constructor
  *
  */

  function DateRange(start, end) {
    this.start = moment(start);
    this.end = moment(end);
  }

  /**
    * Determine if the current interval contains a given moment/date/range.
    * @param {(Moment|Date|DateRange)} other Date to check.
    * @return {!boolean}
  *
  */


  DateRange.prototype.contains = function(other) {
    if (other instanceof DateRange) {
      return this.start <= other.start && this.end >= other.end;
    } else {
      return (this.start <= other && other <= this.end);
    }
  };

  /**
    * @private
  *
  */


  DateRange.prototype._by_string = function(interval, hollaback) {
    var current, _results;
    current = moment(this.start);
    _results = [];
    while (this.contains(current)) {
      hollaback.call(this, current.clone());
      _results.push(current.add(interval, 1));
    }
    return _results;
  };

  /**
    * @private
  *
  */


  DateRange.prototype._by_range = function(range_interval, hollaback) {
    var i, l, _i, _results;
    l = Math.round(this / range_interval);
    if (l === Infinity) {
      return this;
    }
    _results = [];
    for (i = _i = 0; 0 <= l ? _i <= l : _i >= l; i = 0 <= l ? ++_i : --_i) {
      _results.push(hollaback.call(this, moment(this.start.valueOf() + range_interval.valueOf() * i)));
    }
    return _results;
  };

  /**
    * Determine if the current date range overlaps a given date range.
    * @param {!DateRange} range Date range to check.
    * @return {!boolean}
  *
  */


  DateRange.prototype.overlaps = function(range) {
    return this.intersect(range) !== null;
  };

  /**
    * Determine the intersecting periods from one or more date ranges.
    * @param {!DateRange} other A date range to intersect with this one.
    * @return {!DateRange|null}
  *
  */


  DateRange.prototype.intersect = function(other) {
    var _ref, _ref1, _ref2, _ref3, _ref4, _ref5, _ref6, _ref7;
    if (((this.start <= (_ref1 = other.start) && _ref1 < (_ref = this.end)) && _ref < other.end)) {
      return new DateRange(other.start, this.end);
    } else if (((other.start < (_ref3 = this.start) && _ref3 < (_ref2 = other.end)) && _ref2 <= this.end)) {
      return new DateRange(this.start, other.end);
    } else if (((other.start < (_ref5 = this.start) && _ref5 < (_ref4 = this.end)) && _ref4 < other.end)) {
      return this;
    } else if (((this.start <= (_ref7 = other.start) && _ref7 < (_ref6 = other.end)) && _ref6 <= this.end)) {
      return other;
    } else {
      return null;
    }
  };

  /**
    * Subtract one range from another.
    * @param {!DateRange} other A date range to substract from this one.
    * @return {!DateRange[]}
  *
  */


  DateRange.prototype.subtract = function(other) {
    var _ref, _ref1, _ref2, _ref3, _ref4, _ref5, _ref6, _ref7;
    if (this.intersect(other) === null) {
      return [this];
    } else if (((other.start <= (_ref1 = this.start) && _ref1 < (_ref = this.end)) && _ref <= other.end)) {
      return [];
    } else if (((other.start <= (_ref3 = this.start) && _ref3 < (_ref2 = other.end)) && _ref2 < this.end)) {
      return [new DateRange(other.end, this.end)];
    } else if (((this.start < (_ref5 = other.start) && _ref5 < (_ref4 = this.end)) && _ref4 <= other.end)) {
      return [new DateRange(this.start, other.start)];
    } else if (((this.start < (_ref7 = other.start) && _ref7 < (_ref6 = other.end)) && _ref6 < this.end)) {
      return [new DateRange(this.start, other.start), new DateRange(other.end, this.end)];
    }
  };

  /**
    * Iterate over the date range by a given date range, executing a function
    * for each sub-range.
    * @param {!DateRange|String} range     Date range to be used for iteration
    *                                      or shorthand string (shorthands:
    *                                      http://momentjs.com/docs/#/manipulating/add/)
    * @param {!function(Moment)} hollaback Function to execute for each sub-range.
    * @return {!boolean}
  *
  */


  DateRange.prototype.by = function(range, hollaback) {
    if (typeof range === 'string') {
      this._by_string(range, hollaback);
    } else {
      this._by_range(range, hollaback);
    }
    return this;
  };

  /**
    * Date range in milliseconds. Allows basic coercion math of date ranges.
    * @return {!number}
  *
  */


  DateRange.prototype.valueOf = function() {
    return this.end - this.start;
  };

  /**
    * Date range toDate
    * @return  {!Array}
  *
  */


  DateRange.prototype.toDate = function() {
    return [this.start.toDate(), this.end.toDate()];
  };

  /**
    * Determine if this date range is the same as another.
    * @param {!DateRange} other Another date range to compare to.
    * @return {!boolean}
  *
  */


  DateRange.prototype.isSame = function(other) {
    return this.start.isSame(other.start) && this.end.isSame(other.end);
  };

  /**
    * Return the difference of the end vs start.
    *   - To get the difference in milliseconds, use range#diff
    *   - To get the difference in another unit of measurement, pass that measurement as the second argument.
    * @return milliseconds if no measure is passed in, otherwise an increment of measure
  *
  */


  DateRange.prototype.diff = function(unit) {
    if (unit == null) {
      unit = void 0;
    }
    return this.end.diff(this.start, unit);
  };

  return DateRange;

})();

/**
  * Build a date range.
  * @param {(Moment|Date)} start Start of range.
  * @param {(Moment|Date)} end   End of range.
  * @this {Moment}
  * @return {!DateRange}
*
*/


moment.fn.range = function(start, end) {
  if (start in INTERVALS) {
    return new DateRange(moment(this).startOf(start), moment(this).endOf(start));
  } else {
    return new DateRange(start, end);
  }
};

/**
  * Build a date range.
  * @param {(Moment|Date)} start Start of range.
  * @param {(Moment|Date)} end   End of range.
  * @this {Moment}
  * @return {!DateRange}
*
*/


moment.range = function(start, end) {
  return new DateRange(start, end);
};

/**
  * Check if the current moment is within a given date range.
  * @param {!DateRange} range Date range to check.
  * @this {Moment}
  * @return {!boolean}
*
*/


moment.fn.within = function(range) {
  return range.contains(this._d);
};

    return moment;
}));

/* global chatty */

chatty('\033[1;32m+ MongoDB Shell Extensions (0.2.7) by Gabriele Lana <gabriele.lana@gmail.com>\033[0m')

DBCollection.prototype.last = function(n) {
  return this.find().sort({_id: -1}).limit(n || 1)
}

DBCollection.prototype.first = function(n) {
  return this.find().sort({_id: 1}).limit(n || 1)
}

DBQuery.prototype.tocsv = function() {
  return tocsv(this)
}

DBQuery.prototype.printcsv = function() {
  return printcsv(this)
}

var CSV = (function(CSV) {

  CSV = function CSV(lines) {
    this.lines = lines
  }

  CSV.prototype.shellPrint = function() {
    this.lines.forEach(function(line) {
      print(line)
    })
  }

  ;_([
    'all', 'any', 'at', 'collect', 'contains', 'countBy', 'detect', 'each', 'eachRight', 'every',
    'filter', 'find', 'findLast', 'findWhere', 'foldl', 'foldr', 'forEach', 'forEachRight',
    'groupBy', 'include', 'indexBy', 'inject', 'invoke', 'map', 'max', 'min', 'pluck', 'reduce',
    'reduceRight', 'reject', 'sample', 'select', 'shuffle', 'size', 'some', 'sortBy', 'toArray',
    'where', 'compact', 'difference', 'drop', 'findIndex', 'findLastIndex', 'first', 'flatten',
    'head', 'indexOf', 'initial', 'intersection', 'last', 'lastIndexOf', 'object', 'pull',
    'range', 'remove', 'rest', 'sortedIndex', 'tail', 'take', 'union', 'uniq', 'unique',
    'unzip', 'without', 'xor', 'zip', 'zipObject'
  ]).forEach(function(method) {
    CSV.prototype[method] = function() {
      return _[method].apply(_, [this.lines].concat(_.toArray(arguments)))
    }
  })

  CSV.prototype.toString = function() {
    return this.lines.join('\n')
  }

  return CSV
})()


var printcsv = function(x) {
  tocsv(x).forEach(function(line) {
    print(line)
  })
}

var tocsv = (function() {
  var flatten = function(o) {
    return _.reduce(o, function(flattened, value, field) {
      if (_.isPlainObject(value)) {
        _.forEach(flatten(value), function(nestedValue, nestedField) {
          flattened[[field, nestedField].join('.')] = nestedValue
        })
      } else {
        flattened[field] = value
      }
      return flattened
    }, {})
  }

  return function(x) {
    var lines = [],
        fieldNames = {},
        encodedDocuments = x.map(function(doc) {
          return _.reduce(flatten(doc), function(values, value, field) {
            fieldNames[field] = true
            values[field] = tojson(value).replace(
              /^(?:ISODate|ObjectId)\((.*)\)$/,
              function(_, contentAsString) {
                return contentAsString
              }
            )
            return values
          }, {})
        })

    fieldNames = _.keys(fieldNames)

    lines.push(fieldNames.join(','))
    encodedDocuments.forEach(function(encodedDocument) {
      lines.push(
        fieldNames.map(function(fieldName) {
          if (encodedDocument[fieldName] !== undefined) {
            return encodedDocument[fieldName]
          }
          return ''
        }).join(',')
      )
    })

    return new CSV(lines)
  }
})()

DBQuery.prototype.reverse = function() {
  this._checkModify();
  if (!this._query.orderby || _.isEmpty(this._query.orderby)) {
    this._addSpecial('orderby', {'$natural': 1});
  }
  for (var field in this._query.orderby) {
    this._query.orderby[field] = this._query.orderby[field] * -1
  }
  return this
}

DBQuery.prototype.last = DBQuery.prototype.tail =
  function(n) {
    return this.reverse().limit(n || 1)
  }

DBQuery.prototype.first = DBQuery.prototype.head =
  function(n) {
    return this.limit(n || 1)
  }

DBQuery.prototype.tojson = function() {
  return tojson(this.toArray())
}

/* global isObject: false */

DBCollection.prototype.distinctAndCount = function(field, query) {
  field = [].concat(field)
  query = query || {}

  var groupById = _([].concat(field)).reduce(function(result, key) {
    result[key.replace(/\./g, '_')] = '$' + key; return result
  }, {})

  var it = this.aggregate(
    {$match: query},
    {$group: {_id: groupById, count: {$sum: 1}}},
    {$project: {values: '$_id', count: 1, _id: 0}}
  )

  var resultIsAnObject = (it.result !== undefined) && (it.ok !== undefined)
  if (resultIsAnObject && it.ok === 0) {
    return it
  }

  var result = it.result || it.toArray()
  return _.reduce(result, function(all, r) {

    var isValidValue =
      _(r.values)
        .chain()
        .values()
        .map(function(value) {
          if (value === null) {
            return {valueOf: function() {return value}}
          }
          return value
        })
        .any(function(value) {
          if (_(value).isArray()) {
            return _(value).all(function(value) {
              return !_(value).isObject()
            })
          }
          // we support values like Number or Date but not {}
          return value.constructor.name !== ''
        })
        .valueOf()

    if (!isValidValue) {
      throw 'distinctAndCount could not work when one or more fields are objects: ' + tojson(r.values)
    }

    var key =
      _(r.values)
        .chain()
        .values()
        .map(function(value) {
          if (value === null) {
            return '#null#'
          }
          if (_(value.valueOf).isFunction()) {
            value = value.valueOf()
          }
          if (_(value).isArray()) {
            value = _(value).sort().valueOf()
          }
          return value
        })
        .valueOf()
        .join(',')

    all[key] = (all[key] || 0) + r.count

    return all
  }, {})
}

DBQuery.prototype.select = function(expression) {
  if (_.isString(expression)) {
    expression = [].concat(expression)
  }
  if (_.isArray(expression)) {
    expression = _.reduce(expression, function(hash, key) {
      hash[key] = key
      return hash
    }, {})
  }
  if (_.isObject(expression)) {
    var originalNextMethod = this.next

    this.next = function() {
      var doc = originalNextMethod.call(this)
      return _.reduce(expression, function(selected, fieldSelector, fieldName) {
        var fieldValue = jsonpath(doc, fieldSelector)
        if (fieldValue && fieldValue.length === 1) {
          fieldValue = fieldValue[0]
        }
        selected[fieldName] = fieldValue
        return selected
      }, {})
    }
  }
  return this
}


/* JSONPath 0.8.0 - XPath for JSON
 *
 * Copyright (c) 2007 Stefan Goessner (goessner.net)
 * Licensed under the MIT (MIT-LICENSE.txt) licence.
 */
function jsonpath(obj, expr, arg) {
   var P = {
      resultType: arg && arg.resultType || 'VALUE',
      notFoundValue: arg && (arg.notFoundValue !== undefined) ? arg.notFoundValue : undefined,
      result: [],
      normalize: function(expr) {
         var subx = [];
         return expr.replace(/[\['](\??\(.*?\))[\]']/g, function($0,$1){return '[#'+(subx.push($1)-1)+']';})
                    .replace(/'?\.'?|\['?/g, ';')
                    .replace(/;;;|;;/g, ';..;')
                    .replace(/;$|'?\]|'$/g, '')
                    .replace(/#([0-9]+)/g, function($0,$1){return subx[$1];});
      },
      asPath: function(path) {
         var x = path.split(';'), p = '$';
         for (var i=1,n=x.length; i<n; i++) {
            p += /^[0-9*]+$/.test(x[i]) ? ('['+x[i]+']') : ('[\''+x[i]+'\']');
         }
         return p;
      },
      store: function(p, v) {
         if (p) {
           P.result[P.result.length] = P.resultType === 'PATH' ? P.asPath(p) : v;
         }
         return !!p;
      },
      trace: function(expr, val, path) {
         if (expr) {
            var x = expr.split(';'), loc = x.shift();
            x = x.join(';');
            if (val && val.hasOwnProperty(loc)) {
               P.trace(x, val[loc], path + ';' + loc);
            } else if (loc === '*') {
               P.walk(loc, x, val, path, function(m,l,x,v,p) {
                 P.trace(m+';'+x,v,p);
               });
            } else if (loc === '..') {
               P.trace(x, val, path);
               P.walk(loc, x, val, path, function(m,l,x,v,p) {
                 typeof v[m] === 'object' && P.trace('..;'+x,v[m],p+';'+m);
               });
            } else if (/,/.test(loc)) { // [name1,name2,...]
               for (var s=loc.split(/'?,'?/),i=0,n=s.length; i<n; i++) {
                  P.trace(s[i]+';'+x, val, path);
               }
            } else if (/^\(.*?\)$/.test(loc)) { // [(expr)]
               P.trace(P.eval(loc, val, path.substr(path.lastIndexOf(';')+1))+';'+x, val, path);
            } else if (/^\?\(.*?\)$/.test(loc)) { // [?(expr)]
               P.walk(loc, x, val, path, function(m,l,x,v,p) {
                 if (P.eval(l.replace(/^\?\((.*?)\)$/,'$1'),v[m],m)) {
                   P.trace(m+';'+x,v,p);
                 }
               });
            } else if (/^(-?[0-9]*):(-?[0-9]*):?([0-9]*)$/.test(loc)) { // [start:end:step]  phyton slice syntax
               P.slice(loc, x, val, path);
            }
         } else {
           P.store(path, val);
         }
      },
      walk: function(loc, expr, val, path, f) {
        if (val instanceof Array) {
          for (var i=0,n=val.length; i<n; i++) {
            if (i in val) {
              f(i,loc,expr,val,path);
            }
          }
        } else if (typeof val === 'object') {
          for (var m in val) {
            if (val.hasOwnProperty(m)) {
              f(m,loc,expr,val,path);
            }
          }
        }
      },
      slice: function(loc, expr, val, path) {
         if (val instanceof Array) {
            var len=val.length, start=0, end=len, step=1;
            loc.replace(
              /^(-?[0-9]*):(-?[0-9]*):?(-?[0-9]*)$/g,
              function($0,$1,$2,$3){
                start=parseInt($1||start);
                end=parseInt($2||end);
                step=parseInt($3||step);
              }
            );
            start = (start < 0) ? Math.max(0,start+len) : Math.min(len,start);
            end   = (end < 0)   ? Math.max(0,end+len)   : Math.min(len,end);
            for (var i=start; i<end; i+=step) {
               P.trace(i+';'+expr, val, path);
            }
         }
      },
      eval: function(x, _v, _vname) {
        try {
          return $ && _v && eval(x.replace(/@/g, '_v'));
        } catch(e) {
          throw new SyntaxError('jsonpath: ' + e.message + ': ' + x.replace(/@/g, '_v').replace(/\^/g, '_a'));
        }
      }
   };

   var $ = obj;
   if (expr && obj && (P.resultType === 'VALUE' || P.resultType === 'PATH')) {
      P.trace(P.normalize(expr).replace(/^\$;/,''), obj, '$');
      return P.result.length ? P.result : P.notFoundValue;
   }
}

_.mixin({
  shellPrint: function(thing) {
    return tojson(thing.valueOf())
  }
})

moment.yesterday = function() {return moment.utc().subtract(1, 'day').startOf('day')}
moment.today = function() {return moment.utc().startOf('day')}
moment.now = function() {return moment.utc()}
moment.tomorrow = function() {return moment.utc().add(1, 'day').startOf('day')}

moment.INTERVALS = ['year', 'month', 'day', 'hour', 'minute', 'second', 'years', 'months', 'days', 'hours', 'minutes', 'seconds']

moment.between = function(start, end) {
  return moment().range(start, end)
}

moment.$today = function() {
  return moment.$between(moment.today())
}

moment.$between = function(fromTime, toTime) {
  toTime = toTime || moment.now()
  return {
    '$gte': fromTime.toDate(),
    '$lte': toTime.toDate()
  }
}

moment.$inDay = function(aDay) {
  return {
    '$gte': moment(aDay).startOf('day').toDate(),
    '$lte': moment(aDay).endOf('day').toDate()
  }
}


;(function() {
  moment.last = dateRangeFromIntervalOfTime(function(quantity, interval) {
    return function() {
      return moment.between(moment.now().subtract(quantity, interval), moment.now())
    }
  })

  moment.next = dateRangeFromIntervalOfTime(function(quantity, interval) {
    return function() {
      return moment.between(moment.now(), moment.now().add(quantity, interval))
    }
  })

  function dateRangeFromIntervalOfTime(apply) {
    return function(quantity) {
      var asString = function() {return quantity + ' of what?'}
      return _.inject(
        moment.INTERVALS,
        function(proxy, interval) {
          return _.tap(proxy, function() {
            proxy[interval] = apply(quantity, interval)
          })
        },
        {toString: asString, tojson: asString}
      )
    }
  }
})()


;(function() {
  moment.INTERVALS.forEach(function(interval) {
    Number.prototype[interval] = function() {return moment.duration(this.valueOf(), interval)}
  })
})()


;(function(Moment) {

  Moment.prototype.toString = function() {
    return this.clone().utc().format('YYYY-MM-DDTHH:mm:ss.SSS[Z]')
  }

  Moment.prototype.tojson = function() {
    return '"' + this.toString() + '"'
  }

  Moment.prototype.tillNow = Moment.prototype.toNow = function() {
    return this.to(moment.now())
  }

  Moment.prototype.to = function(momentInTime) {
    momentInTime = momentInTime || moment.now()
    if (this.isAfter(momentInTime)) {
      return moment.between(momentInTime, this)
    }
    return moment.between(this, momentInTime)
  }

})(moment().constructor)


;(function(Duration) {

  Duration.prototype.startingNow = function() {
    return this.startingAt(/* now is implicit */)
  }

  Duration.prototype.endingNow = function() {
    return this.endingAt(/* now is implicit */)
  }

  Duration.prototype.startingAt = function(startingAt) {
    var endingAt = (startingAt ? moment(startingAt) : moment.now()).add(this)
    return moment.between(startingAt, endingAt)
  }

  Duration.prototype.endingAt = function(endingAt) {
    var startingAt = (endingAt ? moment(endingAt) : moment.now()).subtract(this)
    return moment.between(startingAt, endingAt)
  }

  Duration.prototype.since = function() {
    return this.after(/* now is implicit */)
  }

  Duration.prototype.ago = function() {
    return this.before(/* now is implicit */)
  }

  Duration.prototype.after = function(momentInTime) {
    momentInTime = (momentInTime ? moment(momentInTime) : moment.now())
    return momentInTime.add(this)
  }

  Duration.prototype.before = function(momentInTime) {
    momentInTime = (momentInTime ? moment(momentInTime) : moment.now())
    return momentInTime.subtract(this)
  }

  Duration.prototype.toString = Duration.prototype.humanize
  Duration.prototype.tojson = function() {
    return '"' + this.toString.apply(this, arguments) + '"'
  }

})(moment.duration().constructor)


;(function(DateRange) {

  DateRange.prototype.forEach = function(duration, callback) {
    duration = (typeof duration === 'string') ? moment.duration(1, duration) : duration
    if (!callback) {
      var moments = []
      this.by(duration.startingAt(this.start), function(moment) {
        moments.push(moment)
      })
      moments._ = _(moments)
      return moments
    }
    this.by(duration.startingAt(this.start), callback)
  }

  DateRange.prototype.duration = function() {
    return moment.duration(this.start.diff(this.end))
  }

  DateRange.prototype.toString = function() {
    return [this.start.toString(), this.end.toString()].join('/')
  }

  DateRange.prototype.tojson = function() {
    return '"' + this.toString() + '"'
  }

})(moment().range().constructor)

DBQuery.prototype.save = function(collection) {
  collection = (typeof collection === 'string') ? this._db.getCollection(collection) : collection
  collection = collection || this._db.createTemporaryCollection()
  assert(collection && collection.constructor.name === 'DBCollection', 'need a collection')
  while (this.hasNext()) {
    collection.save(this.next())
  }
  return collection
}

DB.prototype.collection = function() {
  var _arguments = Array.prototype.slice.call(arguments)
  if (_arguments.length === 2 && _.isString(_arguments[0]) && _.isFunction(_arguments[1])) {
    var collection = this.getCollection(_arguments[0]),
        callback = _arguments[1],
        result = callback(collection)
    return result === undefined ? collection : result
  }
  if (_arguments.length >= 1 && _.isString(_arguments[0])) {
    return this.getCollection(_arguments[0])
  }
  if (_arguments.length >= 1 && _.isFunction(_arguments[0])) {
    return this.createTemporaryCollection(_arguments[0])
  }
  return this
}

DB.prototype.createTemporaryCollection = function(callback, options) {
  var uniquePrefixedName = '__t' + (new ObjectId().valueOf()),
      collection = this.getCollection(uniquePrefixedName),
      aCallbackIsGiven = !!callback,
      result = collection

  options = _({deleteAfter: aCallbackIsGiven}, options)
  try {
    if (aCallbackIsGiven) {
      result = callback(collection)
      if ((result === undefined) && !options.deleteAfter) {
        result = collection
      }
    }
  } finally {
    if (options.deleteAfter) {
      collection.drop()
    }
  }

  return result
}

DB.prototype.getCollections = function() {
  return _(this.getCollectionNames()).map(_.bind(this.getCollection, this)).valueOf()
}

DB.prototype.getTemporaryCollections = function() {
  return _(this.getCollections()).filter(function(c) {return c.isTemporary()}).valueOf()
}

DB.prototype.dropTemporaryCollections = function() {
  this.getTemporaryCollections().forEach(function(c) {
    c.drop()
  })
  return true
}

DBCollection.prototype.isTemporary = function() {
  return this.getName().substr(0, 3) === '__t'
}