<!DOCTYPE html> <html> <head> <title>helpers.coffee</title> <meta http-equiv="content-type" content="text/html; charset=UTF-8"> <meta name="viewport" content="width=device-width, target-densitydpi=160dpi, initial-scale=1.0; maximum-scale=1.0; user-scalable=0;"> <link rel="stylesheet" media="all" href="docco.css" /> </head> <body> <div id="container"> <div id="background"></div> <ul id="jump_to"> <li> <a class="large" href="javascript:void(0);">Jump To …</a> <a class="small" href="javascript:void(0);">+</a> <div id="jump_wrapper"> <div id="jump_page"> <a class="source" href="browser.html"> browser.coffee </a> <a class="source" href="cake.html"> cake.coffee </a> <a class="source" href="coffee-script.html"> coffee-script.coffee </a> <a class="source" href="command.html"> command.coffee </a> <a class="source" href="grammar.html"> grammar.coffee </a> <a class="source" href="helpers.html"> helpers.coffee </a> <a class="source" href="index.html"> index.coffee </a> <a class="source" href="lexer.html"> lexer.coffee </a> <a class="source" href="nodes.html"> nodes.coffee </a> <a class="source" href="optparse.html"> optparse.coffee </a> <a class="source" href="repl.html"> repl.coffee </a> <a class="source" href="rewriter.html"> rewriter.coffee </a> <a class="source" href="scope.html"> scope.litcoffee </a> <a class="source" href="sourcemap.html"> sourcemap.litcoffee </a> </div> </li> </ul> <ul class="sections"> <li id="title"> <div class="annotation"> <h1>helpers.coffee</h1> </div> </li> <li id="section-1"> <div class="annotation"> <div class="pilwrap "> <a class="pilcrow" href="#section-1">¶</a> </div> <p>This file contains the common helper functions that we'd like to share among the <strong>Lexer</strong>, <strong>Rewriter</strong>, and the <strong>Nodes</strong>. Merge objects, flatten arrays, count characters, that sort of thing. </p> </div> </li> <li id="section-2"> <div class="annotation"> <div class="pilwrap "> <a class="pilcrow" href="#section-2">¶</a> </div> <p>Peek at the beginning of a given string to see if it matches a sequence. </p> </div> <div class="content"><div class='highlight'><pre>exports.<span class="function"><span class="title">starts</span></span> = (string, literal, start) -> literal <span class="keyword">is</span> string.substr start, literal.length</pre></div></div> </li> <li id="section-3"> <div class="annotation"> <div class="pilwrap "> <a class="pilcrow" href="#section-3">¶</a> </div> <p>Peek at the end of a given string to see if it matches a sequence. </p> </div> <div class="content"><div class='highlight'><pre>exports.<span class="function"><span class="title">ends</span></span> = (string, literal, back) -> len = literal.length literal <span class="keyword">is</span> string.substr string.length - len - (back <span class="keyword">or</span> <span class="number">0</span>), len</pre></div></div> </li> <li id="section-4"> <div class="annotation"> <div class="pilwrap "> <a class="pilcrow" href="#section-4">¶</a> </div> <p>Repeat a string <code>n</code> times. </p> </div> <div class="content"><div class='highlight'><pre>exports.repeat = <span class="function"><span class="title">repeat</span></span> = (str, n) -></pre></div></div> </li> <li id="section-5"> <div class="annotation"> <div class="pilwrap "> <a class="pilcrow" href="#section-5">¶</a> </div> <p>Use clever algorithm to have O(log(n)) string concatenation operations. </p> </div> <div class="content"><div class='highlight'><pre> res = <span class="string">''</span> <span class="keyword">while</span> n > <span class="number">0</span> res += str <span class="keyword">if</span> n & <span class="number">1</span> n >>>= <span class="number">1</span> str += str res</pre></div></div> </li> <li id="section-6"> <div class="annotation"> <div class="pilwrap "> <a class="pilcrow" href="#section-6">¶</a> </div> <p>Trim out all falsy values from an array. </p> </div> <div class="content"><div class='highlight'><pre>exports.<span class="function"><span class="title">compact</span></span> = (array) -> item <span class="keyword">for</span> item <span class="keyword">in</span> array <span class="keyword">when</span> item</pre></div></div> </li> <li id="section-7"> <div class="annotation"> <div class="pilwrap "> <a class="pilcrow" href="#section-7">¶</a> </div> <p>Count the number of occurrences of a string in a string. </p> </div> <div class="content"><div class='highlight'><pre>exports.<span class="function"><span class="title">count</span></span> = (string, substr) -> num = pos = <span class="number">0</span> <span class="keyword">return</span> <span class="number">1</span>/<span class="number">0</span> <span class="keyword">unless</span> substr.length num++ <span class="keyword">while</span> pos = <span class="number">1</span> + string.indexOf substr, pos num</pre></div></div> </li> <li id="section-8"> <div class="annotation"> <div class="pilwrap "> <a class="pilcrow" href="#section-8">¶</a> </div> <p>Merge objects, returning a fresh copy with attributes from both sides. Used every time <code>Base#compile</code> is called, to allow properties in the options hash to propagate down the tree without polluting other branches. </p> </div> <div class="content"><div class='highlight'><pre>exports.<span class="function"><span class="title">merge</span></span> = (options, overrides) -> extend (extend {}, options), overrides</pre></div></div> </li> <li id="section-9"> <div class="annotation"> <div class="pilwrap "> <a class="pilcrow" href="#section-9">¶</a> </div> <p>Extend a source object with the properties of another object (shallow copy). </p> </div> <div class="content"><div class='highlight'><pre>extend = exports.<span class="function"><span class="title">extend</span></span> = (object, properties) -> <span class="keyword">for</span> key, val <span class="keyword">of</span> properties object[key] = val object</pre></div></div> </li> <li id="section-10"> <div class="annotation"> <div class="pilwrap "> <a class="pilcrow" href="#section-10">¶</a> </div> <p>Return a flattened version of an array. Handy for getting a list of <code>children</code> from the nodes. </p> </div> <div class="content"><div class='highlight'><pre>exports.flatten = <span class="function"><span class="title">flatten</span></span> = (array) -> flattened = [] <span class="keyword">for</span> element <span class="keyword">in</span> array <span class="keyword">if</span> element <span class="keyword">instanceof</span> Array flattened = flattened.concat flatten element <span class="keyword">else</span> flattened.push element flattened</pre></div></div> </li> <li id="section-11"> <div class="annotation"> <div class="pilwrap "> <a class="pilcrow" href="#section-11">¶</a> </div> <p>Delete a key from an object, returning the value. Useful when a node is looking for a particular method in an options hash. </p> </div> <div class="content"><div class='highlight'><pre>exports.<span class="function"><span class="title">del</span></span> = (obj, key) -> val = obj[key] <span class="keyword">delete</span> obj[key] val</pre></div></div> </li> <li id="section-12"> <div class="annotation"> <div class="pilwrap "> <a class="pilcrow" href="#section-12">¶</a> </div> <p>Gets the last item of an array(-like) object. </p> </div> <div class="content"><div class='highlight'><pre>exports.last = <span class="function"><span class="title">last</span></span> = (array, back) -> array[array.length - (back <span class="keyword">or</span> <span class="number">0</span>) - <span class="number">1</span>]</pre></div></div> </li> <li id="section-13"> <div class="annotation"> <div class="pilwrap "> <a class="pilcrow" href="#section-13">¶</a> </div> <p>Typical Array::some </p> </div> <div class="content"><div class='highlight'><pre>exports.some = Array::some ? (fn) -> <span class="keyword">return</span> <span class="literal">true</span> <span class="keyword">for</span> e <span class="keyword">in</span> <span class="keyword">this</span> <span class="keyword">when</span> fn e <span class="literal">false</span></pre></div></div> </li> <li id="section-14"> <div class="annotation"> <div class="pilwrap "> <a class="pilcrow" href="#section-14">¶</a> </div> <p>Simple function for inverting Literate CoffeeScript code by putting the documentation in comments, producing a string of CoffeeScript code that can be compiled "normally". </p> </div> <div class="content"><div class='highlight'><pre>exports.<span class="function"><span class="title">invertLiterate</span></span> = (code) -> maybe_code = <span class="literal">true</span> lines = <span class="keyword">for</span> line <span class="keyword">in</span> code.split(<span class="string">'\n'</span>) <span class="keyword">if</span> maybe_code <span class="keyword">and</span> <span class="regexp">/^([ ]{4}|[ ]{0,3}\t)/</span>.test line line <span class="keyword">else</span> <span class="keyword">if</span> maybe_code = <span class="regexp">/^\s*$/</span>.test line line <span class="keyword">else</span> <span class="string">'# '</span> + line lines.join <span class="string">'\n'</span></pre></div></div> </li> <li id="section-15"> <div class="annotation"> <div class="pilwrap "> <a class="pilcrow" href="#section-15">¶</a> </div> <p>Merge two jison-style location data objects together. If <code>last</code> is not provided, this will simply return <code>first</code>. </p> </div> <div class="content"><div class='highlight'><pre><span class="function"><span class="title">buildLocationData</span></span> = (first, last) -> <span class="keyword">if</span> <span class="keyword">not</span> last first <span class="keyword">else</span> first_line: first.first_line first_column: first.first_column last_line: last.last_line last_column: last.last_column</pre></div></div> </li> <li id="section-16"> <div class="annotation"> <div class="pilwrap "> <a class="pilcrow" href="#section-16">¶</a> </div> <p>This returns a function which takes an object as a parameter, and if that object is an AST node, updates that object's locationData. The object is returned either way. </p> </div> <div class="content"><div class='highlight'><pre>exports.<span class="function"><span class="title">addLocationDataFn</span></span> = (first, last) -> (obj) -> <span class="keyword">if</span> ((<span class="keyword">typeof</span> obj) <span class="keyword">is</span> <span class="string">'object'</span>) <span class="keyword">and</span> (!!obj[<span class="string">'updateLocationDataIfMissing'</span>]) obj.updateLocationDataIfMissing buildLocationData(first, last) <span class="keyword">return</span> obj</pre></div></div> </li> <li id="section-17"> <div class="annotation"> <div class="pilwrap "> <a class="pilcrow" href="#section-17">¶</a> </div> <p>Convert jison location data to a string. <code>obj</code> can be a token, or a locationData. </p> </div> <div class="content"><div class='highlight'><pre>exports.<span class="function"><span class="title">locationDataToString</span></span> = (obj) -> <span class="keyword">if</span> (<span class="string">"2"</span> <span class="keyword">of</span> obj) <span class="keyword">and</span> (<span class="string">"first_line"</span> <span class="keyword">of</span> obj[<span class="number">2</span>]) <span class="keyword">then</span> locationData = obj[<span class="number">2</span>] <span class="keyword">else</span> <span class="keyword">if</span> <span class="string">"first_line"</span> <span class="keyword">of</span> obj <span class="keyword">then</span> locationData = obj <span class="keyword">if</span> locationData <span class="string">"<span class="subst">#{locationData.first_line + <span class="number">1</span>}</span>:<span class="subst">#{locationData.first_column + <span class="number">1</span>}</span>-"</span> + <span class="string">"<span class="subst">#{locationData.last_line + <span class="number">1</span>}</span>:<span class="subst">#{locationData.last_column + <span class="number">1</span>}</span>"</span> <span class="keyword">else</span> <span class="string">"No location data"</span></pre></div></div> </li> <li id="section-18"> <div class="annotation"> <div class="pilwrap "> <a class="pilcrow" href="#section-18">¶</a> </div> <p>A <code>.coffee.md</code> compatible version of <code>basename</code>, that returns the file sans-extension. </p> </div> <div class="content"><div class='highlight'><pre>exports.<span class="function"><span class="title">baseFileName</span></span> = (file, stripExt = <span class="literal">no</span>, useWinPathSep = <span class="literal">no</span>) -> pathSep = <span class="keyword">if</span> useWinPathSep <span class="keyword">then</span> <span class="regexp">/\\|\// else /\//</span> parts = file.split(pathSep) file = parts[parts.length - <span class="number">1</span>] <span class="keyword">return</span> file <span class="keyword">unless</span> stripExt parts = file.split(<span class="string">'.'</span>) parts.pop() parts.pop() <span class="keyword">if</span> parts[parts.length - <span class="number">1</span>] <span class="keyword">is</span> <span class="string">'coffee'</span> <span class="keyword">and</span> parts.length > <span class="number">1</span> parts.join(<span class="string">'.'</span>)</pre></div></div> </li> <li id="section-19"> <div class="annotation"> <div class="pilwrap "> <a class="pilcrow" href="#section-19">¶</a> </div> <p>Determine if a filename represents a CoffeeScript file. </p> </div> <div class="content"><div class='highlight'><pre>exports.<span class="function"><span class="title">isCoffee</span></span> = (file) -> <span class="regexp">/\.((lit)?coffee|coffee\.md)$/</span>.test file</pre></div></div> </li> <li id="section-20"> <div class="annotation"> <div class="pilwrap "> <a class="pilcrow" href="#section-20">¶</a> </div> <p>Determine if a filename represents a Literate CoffeeScript file. </p> </div> <div class="content"><div class='highlight'><pre>exports.<span class="function"><span class="title">isLiterate</span></span> = (file) -> <span class="regexp">/\.(litcoffee|coffee\.md)$/</span>.test file</pre></div></div> </li> <li id="section-21"> <div class="annotation"> <div class="pilwrap "> <a class="pilcrow" href="#section-21">¶</a> </div> <p>Throws a SyntaxError with a source file location data attached to it in a property called <code>location</code>. </p> </div> <div class="content"><div class='highlight'><pre>exports.<span class="function"><span class="title">throwSyntaxError</span></span> = (message, location) -> location.last_line ?= location.first_line location.last_column ?= location.first_column error = <span class="keyword">new</span> SyntaxError message error.location = location <span class="keyword">throw</span> error</pre></div></div> </li> <li id="section-22"> <div class="annotation"> <div class="pilwrap "> <a class="pilcrow" href="#section-22">¶</a> </div> <p>Creates a nice error message like, following the "standard" format </p> <p><filename>:<line>:<col>: <message> plus the line with the error and a marker showing where the error is. </p> </div> <div class="content"><div class='highlight'><pre>exports.<span class="function"><span class="title">prettyErrorMessage</span></span> = (error, fileName, code, useColors) -> <span class="keyword">return</span> error.stack <span class="keyword">or</span> <span class="string">"<span class="subst">#{error}</span>"</span> <span class="keyword">unless</span> error.location {first_line, first_column, last_line, last_column} = error.location codeLine = code.split(<span class="string">'\n'</span>)[first_line] start = first_column</pre></div></div> </li> <li id="section-23"> <div class="annotation"> <div class="pilwrap "> <a class="pilcrow" href="#section-23">¶</a> </div> <p>Show only the first line on multi-line errors. </p> </div> <div class="content"><div class='highlight'><pre> end = <span class="keyword">if</span> first_line <span class="keyword">is</span> last_line <span class="keyword">then</span> last_column + <span class="number">1</span> <span class="keyword">else</span> codeLine.length marker = repeat(<span class="string">' '</span>, start) + repeat(<span class="string">'^'</span>, end - start) <span class="keyword">if</span> useColors <span class="function"><span class="title">colorize</span></span> = (str) -> <span class="string">"\x1B[1;31m<span class="subst">#{str}</span>\x1B[0m"</span> codeLine = codeLine[...start] + colorize(codeLine[start...end]) + codeLine[end..] marker = colorize marker message = <span class="string">""" <span class="subst">#{fileName}</span>:<span class="subst">#{first_line + <span class="number">1</span>}</span>:<span class="subst">#{first_column + <span class="number">1</span>}</span>: error: <span class="subst">#{error.message}</span> <span class="subst">#{codeLine}</span> <span class="subst">#{marker}</span> """</span></pre></div></div> </li> <li id="section-24"> <div class="annotation"> <div class="pilwrap "> <a class="pilcrow" href="#section-24">¶</a> </div> <p>Uncomment to add stacktrace. message += "\n#{error.stack}" </p> </div> <div class="content"><div class='highlight'><pre> message</pre></div></div> </li> </ul> </div> </body> </html>