factor out unlist(lapply())

R/fuse.R

@@ -84,7 +84,7 @@ crack = function(input, text = NULL) {
     j = grepl(rx_inline, m[9, ])
   }
   m = m[, j, drop = FALSE]
-  n_start = unlist(lapply(res, function(x) x$lines[1]))  # starting line numbers
+  n_start = uapply(res, function(x) x$lines[1]))  # starting line numbers
   j = findInterval(m[3, ], n_start)  # find which block each inline code belongs to
   for (i in seq_len(ncol(m))) {
     b = res[[j[i]]]; l = b$lines
@@ -488,7 +488,7 @@ fiss = function(input, output = '.R', text = NULL) {
   output = auto_output(input, output, NULL)
   blocks = crack(input, text)
   # TODO: what should we do for non-R code? also consider eval=FALSE and error=TRUE
-  res = unlist(lapply(blocks, function(b) {
+  res = uapply(blocks, function(b) {
     if (b$type == 'code_chunk' && !isFALSE(b$options$purl) && b$options$engine == 'r')
       c(b$source, '')
   }))
@@ -637,7 +637,7 @@ fuse_code = function(x, blocks) {
   }
 
   # fuse child documents (empty the `child` option to avoid infinite recursion)
-  if (length(opts$child)) return(unlist(lapply(reactor(child = NULL)$child, function(.) {
+  if (length(opts$child)) return(uapply(reactor(child = NULL)$child, function(.) {
     child = .env$child; .env$child = TRUE; on.exit(.env$child <- child)
     fuse(., output = 'markdown', envir = fuse_env(), quiet = TRUE)
   })))
@@ -656,7 +656,7 @@ fuse_code = function(x, blocks) {
   } else if (test_source('code')) {
     x$source = opts$code
   } else if (test_source('ref.label')) {
-    x$source = unlist(lapply(blocks[opts$ref.label], `[[`, 'source'))
+    x$source = uapply(blocks[opts$ref.label], `[[`, 'source'))
   }
 
   lab = opts$label

R/package.R

@@ -80,7 +80,7 @@ vig_filter = function(ifile, encoding) {
   res = lapply(res, function(x) {
     if (x$type == 'code_chunk') return(rep('', length(x$source)))
     if (is.character(x$source)) x$source else {
-      one_string(unlist(lapply(x$source, function(s) {
+      one_string(uapply(x$source, function(s) {
         if (is.character(s)) s else ''
       })), '')
     }

R/utils.R

@@ -27,6 +27,8 @@ dropNULL = function(x) x[!vapply(x, is.null, logical(1))]
 
 is_lang = function(x) is.symbol(x) || is.language(x)
 
+uapply = function(...) unlist(lapply(...))
+
 #' Convert some ASCII strings to HTML entities
 #'
 #' Transform ASCII strings `(c)` (copyright), `(r)` (registered trademark),
@@ -338,7 +340,7 @@ lang_files = function(package, path, langs) {
     if (length(l) == 0) return()
     # check if language files exist on CDN
     d = paste0(dirname(u), '/languages/')
-    l1 = unlist(lapply(l, function(z) {
+    l1 = uapply(l, function(z) {
       if (downloadable(sprintf('%s%s.min.js', d, z))) z
     }))
     l2 = setdiff(l, l1)
@@ -358,7 +360,7 @@ lang_files = function(package, path, langs) {
     x = x[1:2]
     x = lapply(match_full(x, '([[:alnum:]_-]+):(\\["[^]]+\\]|"[^"]+")'), function(z) {
       z = gsub('[]["]', '', z)
-      unlist(lapply(strsplit(z, '[:,]'), function(y) {
+      uapply(strsplit(z, '[:,]'), function(y) {
         set_names(list(y[-1]), y[1])
       }), recursive = FALSE)
     })
@@ -373,12 +375,12 @@ lang_files = function(package, path, langs) {
       c(lapply(deps, resolve_deps), lang)
     }
     # all languages required for this page
-    l1 = unique(unlist(lapply(langs, resolve_deps)))
+    l1 = unique(uapply(langs, resolve_deps)))
     # languages that are officially supported
     l2 = c(names(x1), unlist(x1), x2)
     # for unknown languages, check if they exist on CDN
     d = sub('/plugins/.+', '/components/', u)
-    l3 = unlist(lapply(setdiff(l1, l2), function(z) {
+    l3 = uapply(setdiff(l1, l2), function(z) {
       if (!downloadable(sprintf('%sprism-%s.min.js', d, z))) z
     }))
     l4 = setdiff(l1, l3)
@@ -417,7 +419,7 @@ add_citation = function(x, bib, format = 'html') {
     '(?<!\\{)(\\{\\[\\}@[-;@ [:alnum:]]+\\{\\]\\}|@[-[:alnum:]]+)'
   # [@key] for citep, and @key for citet
   x = match_replace(x, r, function(z) {
-    z2 = unlist(lapply(strsplit(z, '[;@ {}]+'), function(keys) {
+    z2 = uapply(strsplit(z, '[;@ {}]+'), function(keys) {
       bracket = any(grepl('^\\[', keys))
       if (bracket) keys = gsub('^\\[|\\]$', '', keys)
       keys = keys[keys != '']
@@ -467,7 +469,7 @@ cite_link = function(key, text, class = '') {
 # html bibliography
 bib_html = function(bib, keys) {
   bib = sort(bib[unique(keys)])
-  keys = unlist(lapply(bib, function(x) attr(unclass(x)[[1]], 'key')))
+  keys = uapply(bib, function(x) attr(unclass(x)[[1]], 'key')))
   res = format(bib, 'html')
   paste0('<p id="ref-', keys, '"', sub('^<p', '', res))
 }
@@ -928,7 +930,7 @@ jsd_version = local({
   }
 })
 
-jsd_versions = function(pkgs) unlist(lapply(pkgs, jsd_version))
+jsd_versions = function(pkgs) uapply(pkgs, jsd_version))
 
 # resolve the implicit latest version to current latest version
 jsd_resolve = function(x) {
@@ -1071,7 +1073,7 @@ base64_url = function(url, code, ext) {
     if (length(p) == 1) code = match_replace(
       code, '(?<=src:\'url\\(")(%%URL%%/[^"]+)(?="\\))', function(u) {
         u = sub('%%URL%%', paste(d, p, sep = '/'), u, fixed = TRUE)
-        unlist(lapply(u, function(x) download_cache$get(x, 'base64')))
+        uapply(u, function(x) download_cache$get(x, 'base64')))
       }
     ) else warning(
       'Unable to determine the font path in MathJax. Please report an issue to ',
@@ -1087,7 +1089,7 @@ base64_url = function(url, code, ext) {
       z3 = gsub(r, '\\3', z)
       i = !is_https(z2)
       z2[i] = paste(d, z2[i], sep = '/')
-      z2 = unlist(lapply(z2, function(x) {
+      z2 = uapply(z2, function(x) {
         if (is_https(x)) download_cache$get(x, 'base64') else base64_uri(x)
       }))
       paste0(z1, z2, z3)