Explanation
I wrote this scheme interpreter primarily as a learning experiment. It borrows heavily from Peter Norvig's lis.py scheme interpreter for Python. It can be used in the browser and in node.js.
Usage
Instantiate an interpreter like this:
var scheme = require('./scheme.js');
var S = new scheme.Interpreter();
Use the interpreter object like this:
S.parse_eval('(+ 2 2)'); // returns 4
S.parse_eval( '(define facto '+
'(lambda (x) '+
'(if (<= x 1) '+
'1'+
'(* x (facto (- x 1) )))))' );
S.parse_eval('(facto 5)'); // returns 120
REPL
There is also a REPL for node, which can be invoked like this:
node repl
s>>> (+ 2 2)
4
Tests
There is a small set of tests which can be invoked using node:
node test
License: MIT
Copyright (c) 2013 Peter Boyer
Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
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