966 lines
52 KiB
HTML
966 lines
52 KiB
HTML
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<!DOCTYPE html>
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<html>
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<head>
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<meta http-equiv="content-type" content="text/html;charset=UTF-8" />
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<title>CoffeeScript</title>
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<link rel="stylesheet" type="text/css" href="documentation/css/docs.css" />
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<link rel="stylesheet" type="text/css" href="documentation/css/idle.css" />
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</head>
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<body>
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<div class="container">
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<h1><sub style="font-size: 100px;">☕</sub> CoffeeScript</h1>
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<p>
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CoffeeScript is a little language that compiles into JavaScript. Think
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of it as JavaScript's less ostentatious kid brother — the same genes,
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roughly the same height, but a different sense of style. Apart from a handful of
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bonus goodies, statements in CoffeeScript correspond one-to-one with their
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equivalent in JavaScript, it's just another way of saying it.
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</p>
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<p>
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<b>Disclaimer:</b>
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CoffeeScript is just for fun and seriously alpha. I'm sure that there are still
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plenty of holes in the lexer and leaks in the syntax. <i>There is no guarantee,
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explicit or implied, of its suitability for any purpose.</i> That said,
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it compiles into clean JavaScript (the good parts) that can use existing
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JavaScript libraries seamlessly, and passes through
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<a href="http://www.jslint.com/">JSLint</a> without warnings. The compiled
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output is quite readable — pretty-printed, with comments
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preserved intact.
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</p>
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<h2>Table of Contents</h2>
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<p>
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<a href="#overview">Mini Overview</a><br />
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<a href="#installation">Installation and Usage</a><br />
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<a href="#punctuation">Punctuation Primer</a><br />
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<a href="#functions">Functions and Invocation</a><br />
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<a href="#assignment">Assignment</a><br />
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<a href="#objects_and_arrays">Objects and Arrays</a><br />
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<a href="#lexical_scope">Lexical Scoping and Variable Safety</a><br />
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<a href="#conditionals">Conditionals, Ternaries, and Conditional Assignment</a><br />
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<a href="#expressions">Everything is an Expression</a><br />
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<a href="#aliases">Aliases</a><br />
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<a href="#while">While Loops</a><br />
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<a href="#array_comprehensions">Array Comprehensions</a><br />
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<a href="#slice">Slicing Arrays with Ranges</a><br />
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<a href="#inheritance">Inheritance, and Calling Super from a Subclass</a><br />
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<a href="#embedded">Embedded JavaScript</a><br />
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<a href="#switch">Switch/When/Else</a><br />
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<a href="#try">Try/Catch/Finally</a><br />
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<a href="#strings">Multiline Strings</a><br />
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<a href="#resources">Resources</a><br />
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<a href="#contributing">Contributing</a><br />
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<a href="#change_log">Change Log</a><br />
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</p>
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<h2 id="overview">Mini Overview</h2>
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<p><i>CoffeeScript on the left, compiled JavaScript output on the right.</i></p>
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<div class='code'><pre class="idle"><span class="Comment"><span class="Comment">#</span> Assignment:</span>
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number<span class="Keyword">:</span> <span class="Number">42</span>
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opposite_day<span class="Keyword">:</span> <span class="BuiltInConstant">true</span>
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<span class="Comment"><span class="Comment">#</span> Conditions:</span>
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number<span class="Keyword">:</span> <span class="Keyword">-</span><span class="Number">42</span> <span class="Keyword">if</span> opposite_day
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<span class="Comment"><span class="Comment">#</span> Functions:</span>
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<span class="FunctionName">square</span><span class="Keyword">:</span> <span class="FunctionArgument">x</span> <span class="Storage">=></span> x <span class="Keyword">*</span> x
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<span class="Comment"><span class="Comment">#</span> Arrays:</span>
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list<span class="Keyword">:</span> [<span class="Number">1</span>, <span class="Number">2</span>, <span class="Number">3</span>, <span class="Number">4</span>, <span class="Number">5</span>]
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<span class="Comment"><span class="Comment">#</span> Objects:</span>
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math<span class="Keyword">:</span> {
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root<span class="Keyword">:</span> Math.sqrt
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square<span class="Keyword">:</span> square
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<span class="FunctionName">cube</span><span class="Keyword">:</span> <span class="FunctionArgument">x</span> <span class="Storage">=></span> x <span class="Keyword">*</span> square(x)
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}
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<span class="Comment"><span class="Comment">#</span> Array comprehensions:</span>
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cubed_list<span class="Keyword">:</span> math.cube(num) <span class="Keyword">for</span> num <span class="Keyword">in</span> list
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</pre><pre class="idle"><span class="Storage">var</span> __a, __b, __c, __d, cubed_list, list, math, num, number, opposite_day, square;
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<span class="Comment"><span class="Comment">//</span> Assignment:</span>
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number <span class="Keyword">=</span> <span class="Number">42</span>;
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opposite_day <span class="Keyword">=</span> <span class="BuiltInConstant">true</span>;
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<span class="Comment"><span class="Comment">//</span> Conditions:</span>
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<span class="Keyword">if</span> (opposite_day) {
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number <span class="Keyword">=</span> <span class="Keyword">-</span><span class="Number">42</span>;
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}
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<span class="Comment"><span class="Comment">//</span> Functions:</span>
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square <span class="Keyword">=</span> <span class="Storage">function</span> <span class="FunctionName">square</span>(<span class="FunctionArgument">x</span>) {
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<span class="Keyword">return</span> x <span class="Keyword">*</span> x;
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};
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<span class="Comment"><span class="Comment">//</span> Arrays:</span>
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list <span class="Keyword">=</span> [<span class="Number">1</span>, <span class="Number">2</span>, <span class="Number">3</span>, <span class="Number">4</span>, <span class="Number">5</span>];
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<span class="Comment"><span class="Comment">//</span> Objects:</span>
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math <span class="Keyword">=</span> {
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root: <span class="LibraryClassType">Math</span>.sqrt,
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square: square,
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cube: <span class="Storage">function</span> <span class="FunctionName">cube</span>(<span class="FunctionArgument">x</span>) {
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<span class="Keyword">return</span> x <span class="Keyword">*</span> square(x);
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}
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};
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<span class="Comment"><span class="Comment">//</span> Array comprehensions:</span>
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__a <span class="Keyword">=</span> list;
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__c <span class="Keyword">=</span> [];
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<span class="Keyword">for</span> (__b <span class="Keyword">in</span> __a) {
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<span class="Keyword">if</span> (__a.hasOwnProperty(__b)) {
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num <span class="Keyword">=</span> __a[__b];
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__d <span class="Keyword">=</span> math.cube(num);
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__c.<span class="LibraryFunction">push</span>(__d);
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}
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}
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cubed_list <span class="Keyword">=</span> __c;
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</pre><button onclick='javascript: var __a, __b, __c, __d, cubed_list, list, math, num, number, opposite_day, square;
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// Assignment:
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number = 42;
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opposite_day = true;
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// Conditions:
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if (opposite_day) {
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number = -42;
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}
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// Functions:
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square = function square(x) {
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return x * x;
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};
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// Arrays:
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list = [1, 2, 3, 4, 5];
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// Objects:
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math = {
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root: Math.sqrt,
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square: square,
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cube: function cube(x) {
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return x * square(x);
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}
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};
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// Array comprehensions:
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__a = list;
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__c = [];
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for (__b in __a) {
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if (__a.hasOwnProperty(__b)) {
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num = __a[__b];
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__d = math.cube(num);
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__c.push(__d);
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}
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}
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cubed_list = __c;
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;alert(cubed_list);'>run: cubed_list</button><br class='clear' /></div>
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<h2 id="installation">Installation and Usage</h2>
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<p>
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The CoffeeScript compiler is written in pure Ruby, and is available
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as a Ruby Gem.
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</p>
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<pre>
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gem install coffee-script</pre>
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<p>
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Installing the gem provides the <tt>coffee</tt> command, which can
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be used to compile CoffeeScript <tt>.coffee</tt> files into JavaScript, as
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well as debug them. In conjunction with
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<a href="http://narwhaljs.org/">Narwhal</a>, the <tt>coffee</tt>
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command also provides direct evaluation and an interactive REPL.
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When compiling to JavaScript, <tt>coffee</tt> writes the output
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as <tt>.js</tt> files in the same directory by default, but output
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can be customized with the following options:
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</p>
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<table>
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<tr>
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<td width="25%"><code>-i, --interactive</code></td>
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<td>
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Launch an interactive CoffeeScript session.
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Requires <a href="http://narwhaljs.org/">Narwhal</a>.
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</td>
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</tr>
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<tr>
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<td><code>-r, --run</code></td>
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<td>
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Compile and execute the CoffeeScripts without saving the intermediate
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JavaScript. Requires <a href="http://narwhaljs.org/">Narwhal</a>.
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</td>
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</tr>
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<tr>
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<td><code>-o, --output [DIR]</code></td>
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<td>
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Write out all compiled JavaScript files into the specified directory.
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</td>
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</tr>
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<tr>
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<td><code>-w, --watch</code></td>
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<td>
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Watch the modification times of the coffee-scripts, recompiling as
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soon as a change occurs.
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</td>
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</tr>
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<tr>
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<td><code>-p, --print</code></td>
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<td>
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Instead of writing out the JavaScript as a file, print it
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directly to <b>stdout</b>.
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</td>
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</tr>
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<tr>
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<td><code>-l, --lint</code></td>
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<td>
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If the <tt>jsl</tt> (JavaScript Lint) command is installed, use it
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to check the compilation of a CoffeeScript file. (Handy in
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conjunction with <tt>--watch</tt>)
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</td>
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</tr>
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<tr>
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<td><code>-e, --eval</code></td>
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<td>
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Compile and print a little snippet of CoffeeScript directly from the
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command line (or from <b>stdin</b>). For example:<br /><tt>coffee -e "square: x => x * x."</tt>
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</td>
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</tr>
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<tr>
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<td><code>-t, --tokens</code></td>
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<td>
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Instead of parsing the CoffeeScript, just lex it, and print out the
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token stream: <tt>[:IDENTIFIER, "square"], [":", ":"], [:PARAM, "x"]</tt> ...
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</td>
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</tr>
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<tr>
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<td><code>-v, --verbose</code></td>
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<td>
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As the JavaScript is being generated, print out every step of code
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generation, including lexical scope and the node in the
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AST.
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</td>
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</tr>
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<tr>
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<td><code>-n, --no-wrap</code></td>
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<td>
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Compile the JavaScript without the top-level function safety wrapper
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or var declarations, for situations where you want to add every
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variable to global scope.
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</td>
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</tr>
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<tr>
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<td><code>--install-bundle</code></td>
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<td>
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Install the TextMate bundle for CoffeeScript syntax highlighting.
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</td>
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</tr>
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</table>
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<p>
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<b>Examples:</b>
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</p>
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<pre>
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coffee path/to/script.coffee
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coffee --interactive
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coffee --watch --lint experimental.coffee
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coffee --print app/scripts/*.coffee > concatenation.js</pre>
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<h2>Language Reference</h2>
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<p>
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<i>
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This reference is structured so that it can be read from top to bottom,
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if you like. Later sections use ideas and syntax previously introduced.
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Familiarity with JavaScript is assumed.
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In all of the following examples, the source CoffeeScript is provided on
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the left, and the direct compilation into JavaScript is on the right.
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</i>
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</p>
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<p id="punctuation">
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<b class="header">Punctuation Primer</b>
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You don't need to use semicolons <tt>;</tt> to terminate expressions, ending
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the line will do just as well. All other whitespace is
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not significant. Instead of using curly braces <tt>{ }</tt>
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to delimit a block of code, use a period <tt>.</tt> to mark the end of a
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block, for
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<a href="#functions">functions</a>,
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<a href="#conditionals">if-statements</a>,
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<a href="#switch">switch</a>, and <a href="#try">try/catch</a>.
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</p>
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<p id="functions">
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<b class="header">Functions and Invocation</b>
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Functions are defined by a list of parameters, an arrow, and the
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function body. The empty function looks like this: <tt>=>.</tt>
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</p>
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<div class='code'><pre class="idle"><span class="FunctionName">square</span><span class="Keyword">:</span> <span class="FunctionArgument">x</span> <span class="Storage">=></span> x <span class="Keyword">*</span> x
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<span class="FunctionName">cube</span><span class="Keyword">:</span> <span class="FunctionArgument">x</span> <span class="Storage">=></span> square(x) <span class="Keyword">*</span> x
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</pre><pre class="idle"><span class="Storage">var</span> cube, square;
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square <span class="Keyword">=</span> <span class="Storage">function</span> <span class="FunctionName">square</span>(<span class="FunctionArgument">x</span>) {
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<span class="Keyword">return</span> x <span class="Keyword">*</span> x;
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};
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cube <span class="Keyword">=</span> <span class="Storage">function</span> <span class="FunctionName">cube</span>(<span class="FunctionArgument">x</span>) {
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<span class="Keyword">return</span> square(x) <span class="Keyword">*</span> x;
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};
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</pre><button onclick='javascript: var cube, square;
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square = function square(x) {
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return x * x;
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};
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cube = function cube(x) {
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return square(x) * x;
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};
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;alert(cube(5));'>run: cube(5)</button><br class='clear' /></div>
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<p id="assignment">
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<b class="header">Assignment</b>
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Use a colon <tt>:</tt> to assign, as in
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<a href="http://json.org">JSON</a>. Equal signs are only needed for
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mathy things.
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</p>
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<div class='code'><pre class="idle">greeting<span class="Keyword">:</span> <span class="String"><span class="String">"</span>Hello CoffeeScript<span class="String">"</span></span>
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difficulty<span class="Keyword">:</span> <span class="Number">0.5</span>
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</pre><pre class="idle"><span class="Storage">var</span> difficulty, greeting;
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greeting <span class="Keyword">=</span> <span class="String"><span class="String">"</span>Hello CoffeeScript<span class="String">"</span></span>;
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difficulty <span class="Keyword">=</span> <span class="Number">0.5</span>;
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</pre><button onclick='javascript: var difficulty, greeting;
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greeting = "Hello CoffeeScript";
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difficulty = 0.5;
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;alert(greeting);'>run: greeting</button><br class='clear' /></div>
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<p>
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Declarations of new variables are pushed up to the top of the current scope,
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so that assignments may always be used within expressions.
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</p>
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<p id="objects_and_arrays">
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<b class="header">Objects and Arrays</b>
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Object and Array literals look very similar to their JavaScript cousins.
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When you spread out each assignment on a separate line, the commas are
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optional. In this way, assigning object properties looks the same as
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assigning local variables.
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</p>
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<div class='code'><pre class="idle">song<span class="Keyword">:</span> [<span class="String"><span class="String">"</span>do<span class="String">"</span></span>, <span class="String"><span class="String">"</span>re<span class="String">"</span></span>, <span class="String"><span class="String">"</span>mi<span class="String">"</span></span>, <span class="String"><span class="String">"</span>fa<span class="String">"</span></span>, <span class="String"><span class="String">"</span>so<span class="String">"</span></span>]
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ages<span class="Keyword">:</span> {
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max<span class="Keyword">:</span> <span class="Number">10</span>
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ida<span class="Keyword">:</span> <span class="Number">9</span>
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tim<span class="Keyword">:</span> <span class="Number">11</span>
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}
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</pre><pre class="idle"><span class="Storage">var</span> ages, song;
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song <span class="Keyword">=</span> [<span class="String"><span class="String">"</span>do<span class="String">"</span></span>, <span class="String"><span class="String">"</span>re<span class="String">"</span></span>, <span class="String"><span class="String">"</span>mi<span class="String">"</span></span>, <span class="String"><span class="String">"</span>fa<span class="String">"</span></span>, <span class="String"><span class="String">"</span>so<span class="String">"</span></span>];
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ages <span class="Keyword">=</span> {
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max: <span class="Number">10</span>,
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ida: <span class="Number">9</span>,
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tim: <span class="Number">11</span>
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};
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</pre><button onclick='javascript: var ages, song;
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song = ["do", "re", "mi", "fa", "so"];
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ages = {
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max: 10,
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ida: 9,
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tim: 11
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};
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;alert(song.join(","));'>run: song.join(",")</button><br class='clear' /></div>
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<p id="lexical_scope">
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<b class="header">Lexical Scoping and Variable Safety</b>
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The CoffeeScript compiler takes care to make sure that all of your variables
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are properly declared within lexical scope — you never need to write
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<tt>var</tt> yourself.
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</p>
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<div class='code'><pre class="idle">num<span class="Keyword">:</span> <span class="Number">1</span>
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<span class="FunctionName">change_numbers</span><span class="Keyword">:</span> <span class="Storage">=></span>
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num<span class="Keyword">:</span> <span class="Number">2</span>
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new_num<span class="Keyword">:</span> <span class="Number">3</span>
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new_num<span class="Keyword">:</span> change_numbers()
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</pre><pre class="idle"><span class="Storage">var</span> change_numbers, new_num, num;
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num <span class="Keyword">=</span> <span class="Number">1</span>;
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change_numbers <span class="Keyword">=</span> <span class="Storage">function</span> <span class="FunctionName">change_numbers</span>() {
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<span class="Storage">var</span> new_num;
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num <span class="Keyword">=</span> <span class="Number">2</span>;
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<span class="Keyword">return</span> (new_num <span class="Keyword">=</span> <span class="Number">3</span>);
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};
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new_num <span class="Keyword">=</span> change_numbers();
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</pre><button onclick='javascript: var change_numbers, new_num, num;
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num = 1;
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change_numbers = function change_numbers() {
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var new_num;
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num = 2;
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return (new_num = 3);
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};
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new_num = change_numbers();
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;alert(new_num);'>run: new_num</button><br class='clear' /></div>
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<p>
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Notice how the variables are declared with <tt>var</tt> the first time
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they appear. The second reference of <b>num</b>, within the function,
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is not redeclared because <b>num</b> is still in scope. As opposed
|
|
to the second occurrence of <b>new_num</b>, in the last line.
|
|
</p>
|
|
<p>
|
|
Although suppressed within this documentation for clarity, all
|
|
CoffeeScript output is wrapped in an anonymous function:
|
|
<tt>(function(){ ... })();</tt> This safety wrapper, combined with the
|
|
automatic generation of the <tt>var</tt> keyword, make it exceedingly difficult
|
|
to pollute the global namespace by accident.
|
|
</p>
|
|
|
|
<p id="conditionals">
|
|
<b class="header">Conditionals, Ternaries, and Conditional Assignment</b>
|
|
<b>If/else</b> statements can be written without the use of parentheses and
|
|
curly brackets. As with functions and other block expressions, conditionals
|
|
are closed with periods. No period is necessary when using the single-line
|
|
postfix form, with the <tt>if</tt> at the end.
|
|
</p>
|
|
<p>
|
|
CoffeeScript will compile <b>if</b> statements using the ternary operator
|
|
when possible, to make it easier to use the result as an expression.
|
|
</p>
|
|
<div class='code'><pre class="idle">mood<span class="Keyword">:</span> greatly_improved <span class="Keyword">if</span> singing
|
|
|
|
<span class="Keyword">if</span> happy <span class="Keyword">and</span> knows_it
|
|
claps_hands()
|
|
cha_cha_cha()
|
|
|
|
date<span class="Keyword">:</span> <span class="Keyword">if</span> friday <span class="Keyword">then</span> sue <span class="Keyword">else</span> jill
|
|
|
|
expensive <span class="Keyword">||</span><span class="Keyword">=</span> do_the_math()
|
|
</pre><pre class="idle"><span class="Storage">var</span> date, mood;
|
|
<span class="Keyword">if</span> (singing) {
|
|
mood <span class="Keyword">=</span> greatly_improved;
|
|
}
|
|
<span class="Keyword">if</span> (happy <span class="Keyword">&</span><span class="Keyword">&</span> knows_it) {
|
|
claps_hands();
|
|
cha_cha_cha();
|
|
}
|
|
date <span class="Keyword">=</span> friday ? sue : jill;
|
|
expensive <span class="Keyword">=</span> expensive <span class="Keyword">||</span> do_the_math();
|
|
</pre><br class='clear' /></div>
|
|
<p>
|
|
The conditional assignment operators are available: <tt>||=</tt>,
|
|
which only assigns a value to a variable if the variable's current value
|
|
is falsy, and <tt>&&=</tt>, which only replaces the value of
|
|
truthy variables.
|
|
</p>
|
|
|
|
<p id="expressions">
|
|
<b class="header">Everything is an Expression (at least, as much as possible)</b>
|
|
You might have noticed how even though we don't add return statements
|
|
to CoffeeScript functions, they nonetheless return their final value.
|
|
The CoffeeScript compiler tries to make sure that all statements in the
|
|
language can be used as expressions. Watch how the <tt>return</tt> gets
|
|
pushed down into each possible branch of execution, in the function
|
|
below.
|
|
</p>
|
|
<div class='code'><pre class="idle"><span class="FunctionName">grade</span><span class="Keyword">:</span> <span class="FunctionArgument">student</span> <span class="Storage">=></span>
|
|
<span class="Keyword">if</span> student.excellent_work
|
|
<span class="String"><span class="String">"</span>A+<span class="String">"</span></span>
|
|
<span class="Keyword">else</span> <span class="Keyword">if</span> student.okay_stuff
|
|
<span class="Keyword">if</span> student.tried_hard <span class="Keyword">then</span> <span class="String"><span class="String">"</span>B<span class="String">"</span></span> <span class="Keyword">else</span> <span class="String"><span class="String">"</span>B-<span class="String">"</span></span>
|
|
<span class="Keyword">else</span>
|
|
<span class="String"><span class="String">"</span>C<span class="String">"</span></span>
|
|
|
|
eldest<span class="Keyword">:</span> <span class="Keyword">if</span> <span class="Number">24</span> <span class="Keyword">></span> <span class="Number">21</span> <span class="Keyword">then</span> <span class="String"><span class="String">"</span>Liz<span class="String">"</span></span> <span class="Keyword">else</span> <span class="String"><span class="String">"</span>Ike<span class="String">"</span></span>
|
|
</pre><pre class="idle"><span class="Storage">var</span> eldest, grade;
|
|
grade <span class="Keyword">=</span> <span class="Storage">function</span> <span class="FunctionName">grade</span>(<span class="FunctionArgument">student</span>) {
|
|
<span class="Keyword">if</span> (student.excellent_work) {
|
|
<span class="Keyword">return</span> <span class="String"><span class="String">"</span>A+<span class="String">"</span></span>;
|
|
} <span class="Keyword">else</span> <span class="Keyword">if</span> (student.okay_stuff) {
|
|
<span class="Keyword">return</span> student.tried_hard ? <span class="String"><span class="String">"</span>B<span class="String">"</span></span> : <span class="String"><span class="String">"</span>B-<span class="String">"</span></span>;
|
|
} <span class="Keyword">else</span> {
|
|
<span class="Keyword">return</span> <span class="String"><span class="String">"</span>C<span class="String">"</span></span>;
|
|
}
|
|
};
|
|
eldest <span class="Keyword">=</span> <span class="Number">24</span> <span class="Keyword">></span> <span class="Number">21</span> ? <span class="String"><span class="String">"</span>Liz<span class="String">"</span></span> : <span class="String"><span class="String">"</span>Ike<span class="String">"</span></span>;
|
|
</pre><button onclick='javascript: var eldest, grade;
|
|
grade = function grade(student) {
|
|
if (student.excellent_work) {
|
|
return "A+";
|
|
} else if (student.okay_stuff) {
|
|
return student.tried_hard ? "B" : "B-";
|
|
} else {
|
|
return "C";
|
|
}
|
|
};
|
|
eldest = 24 > 21 ? "Liz" : "Ike";
|
|
;alert(eldest);'>run: eldest</button><br class='clear' /></div>
|
|
<p>
|
|
The same mechanism is used to push down assignment through <b>switch</b>
|
|
statements, and <b>if-elses</b> (although the ternary operator is preferred).
|
|
Another part of manipulating assignment statements is
|
|
CoffeeScript's declaration of new variables at the top of the
|
|
current scope. This allows assignment to be used as a piece of an
|
|
expression.
|
|
</p>
|
|
<div class='code'><pre class="idle">six<span class="Keyword">:</span> (one<span class="Keyword">:</span> <span class="Number">1</span>) <span class="Keyword">+</span> (two<span class="Keyword">:</span> <span class="Number">2</span>) <span class="Keyword">+</span> (three<span class="Keyword">:</span> <span class="Number">3</span>)
|
|
</pre><pre class="idle"><span class="Storage">var</span> one, six, three, two;
|
|
six <span class="Keyword">=</span> (one <span class="Keyword">=</span> <span class="Number">1</span>) <span class="Keyword">+</span> (two <span class="Keyword">=</span> <span class="Number">2</span>) <span class="Keyword">+</span> (three <span class="Keyword">=</span> <span class="Number">3</span>);
|
|
</pre><button onclick='javascript: var one, six, three, two;
|
|
six = (one = 1) + (two = 2) + (three = 3);
|
|
;alert(six);'>run: six</button><br class='clear' /></div>
|
|
|
|
<p id="aliases">
|
|
<b class="header">Aliases</b>
|
|
Because the <tt>==</tt> operator frequently causes undesirable coercion,
|
|
is intransitive, and has a different meaning than in other languages,
|
|
CoffeeScript compiles <tt>==</tt> into <tt>===</tt>, and <tt>!=</tt> into
|
|
<tt>!==</tt>.
|
|
In addition, <tt>is</tt> compiles into <tt>===</tt>,
|
|
and <tt>isnt</tt> into <tt>!==</tt>.
|
|
</p>
|
|
<p>
|
|
You can use <tt>not</tt> as an alias for <tt>!</tt>.
|
|
</p>
|
|
<p>
|
|
For logic, <tt>and</tt> compiles to <tt>&&</tt>, and <tt>or</tt>
|
|
into <tt>||</tt>.
|
|
</p>
|
|
<p>
|
|
Instead of a newline or semicolon, <tt>then</tt> can be used to separate
|
|
conditions from expressions, in <b>while</b>,
|
|
<b>if</b>/<b>else</b>, and <b>switch</b>/<b>when</b> statements.
|
|
</p>
|
|
<p>
|
|
As in <a href="http://yaml.org/">YAML</a>, <tt>on</tt> and <tt>yes</tt>
|
|
are the same as boolean <tt>true</tt>, while <tt>off</tt> and <tt>no</tt> are boolean <tt>false</tt>.
|
|
</p>
|
|
<p>
|
|
For single-line statements, <tt>unless</tt> can be used as the inverse of <tt>if</tt>.
|
|
</p>
|
|
<div class='code'><pre class="idle">launch() <span class="Keyword">if</span> ignition <span class="Keyword">is</span> <span class="BuiltInConstant">on</span>
|
|
|
|
volume<span class="Keyword">:</span> <span class="Number">10</span> <span class="Keyword">if</span> band <span class="Keyword">isnt</span> spinal_tap
|
|
|
|
let_the_wild_rumpus_begin() <span class="Keyword">unless</span> answer <span class="Keyword">is</span> <span class="BuiltInConstant">no</span>
|
|
|
|
<span class="Keyword">if</span> car.speed <span class="Keyword"><</span> speed_limit <span class="Keyword">then</span> accelerate()
|
|
</pre><pre class="idle"><span class="Storage">var</span> volume;
|
|
<span class="Keyword">if</span> (ignition <span class="Keyword">===</span> <span class="BuiltInConstant">true</span>) {
|
|
launch();
|
|
}
|
|
<span class="Keyword">if</span> (band <span class="Keyword">!</span><span class="Keyword">==</span> spinal_tap) {
|
|
volume <span class="Keyword">=</span> <span class="Number">10</span>;
|
|
}
|
|
<span class="Keyword">if</span> (<span class="Keyword">!</span>(answer <span class="Keyword">===</span> <span class="BuiltInConstant">false</span>)) {
|
|
let_the_wild_rumpus_begin();
|
|
}
|
|
car.speed <span class="Keyword"><</span> speed_limit ? accelerate() : <span class="BuiltInConstant">null</span>;
|
|
</pre><br class='clear' /></div>
|
|
|
|
<p id="while">
|
|
<b class="header">While Loops</b>
|
|
The only low-level loop that CoffeeScript provides is the while loop.
|
|
</p>
|
|
<div class='code'><pre class="idle"><span class="Keyword">while</span> demand <span class="Keyword">></span> supply
|
|
sell()
|
|
restock()
|
|
|
|
<span class="Keyword">while</span> supply <span class="Keyword">></span> demand <span class="Keyword">then</span> buy()
|
|
</pre><pre class="idle"><span class="Keyword">while</span> (demand <span class="Keyword">></span> supply) {
|
|
sell();
|
|
restock();
|
|
}
|
|
<span class="Keyword">while</span> (supply <span class="Keyword">></span> demand) {
|
|
buy();
|
|
}
|
|
</pre><br class='clear' /></div>
|
|
<p>
|
|
Other JavaScript loops, such as <b>for</b> loops and <b>do-while</b> loops
|
|
can be mimicked by variations on <b>while</b>, but the hope is that you
|
|
won't need to do that with CoffeeScript, either because you're using
|
|
<b>each</b> (<b>forEach</b>) style iterators, or...
|
|
</p>
|
|
|
|
<p id="array_comprehensions">
|
|
<b class="header">Array Comprehensions</b>
|
|
For your looping needs, CoffeeScript provides array comprehensions
|
|
similar to Python's. They replace (and compile into) <b>for</b> loops, with
|
|
optional guard clauses and the value of the current array index.
|
|
Unlike for loops, array comprehensions are expressions, and can be returned
|
|
and assigned. They should be able to handle most places where you otherwise
|
|
would use a loop, <b>each</b>/<b>forEach</b>, <b>map</b>, or <b>select</b>/<b>filter</b>.
|
|
</p>
|
|
<div class='code'><pre class="idle"><span class="Comment"><span class="Comment">#</span> Eat lunch.</span>
|
|
lunch<span class="Keyword">:</span> <span class="Variable">this</span>.eat(food) <span class="Keyword">for</span> food <span class="Keyword">in</span> [<span class="String"><span class="String">'</span>toast<span class="String">'</span></span>, <span class="String"><span class="String">'</span>cheese<span class="String">'</span></span>, <span class="String"><span class="String">'</span>wine<span class="String">'</span></span>]
|
|
|
|
<span class="Comment"><span class="Comment">#</span> Zebra-stripe a table.</span>
|
|
highlight(row) <span class="Keyword">for</span> row, i <span class="Keyword">in</span> table <span class="Keyword">when</span> i <span class="Keyword">%</span> <span class="Number">2</span> <span class="Keyword">is</span> <span class="Number">0</span>
|
|
</pre><pre class="idle"><span class="Storage">var</span> __a, __b, __c, __d, __e, __f, __g, food, i, lunch, row;
|
|
<span class="Comment"><span class="Comment">//</span> Eat lunch.</span>
|
|
__a <span class="Keyword">=</span> [<span class="String"><span class="String">'</span>toast<span class="String">'</span></span>, <span class="String"><span class="String">'</span>cheese<span class="String">'</span></span>, <span class="String"><span class="String">'</span>wine<span class="String">'</span></span>];
|
|
__c <span class="Keyword">=</span> [];
|
|
<span class="Keyword">for</span> (__b <span class="Keyword">in</span> __a) {
|
|
<span class="Keyword">if</span> (__a.hasOwnProperty(__b)) {
|
|
food <span class="Keyword">=</span> __a[__b];
|
|
__d <span class="Keyword">=</span> <span class="Variable">this</span>.eat(food);
|
|
__c.<span class="LibraryFunction">push</span>(__d);
|
|
}
|
|
}
|
|
lunch <span class="Keyword">=</span> __c;
|
|
<span class="Comment"><span class="Comment">//</span> Zebra-stripe a table.</span>
|
|
__e <span class="Keyword">=</span> table;
|
|
__f <span class="Keyword">=</span> [];
|
|
<span class="Keyword">for</span> (i <span class="Keyword">in</span> __e) {
|
|
<span class="Keyword">if</span> (__e.hasOwnProperty(i)) {
|
|
row <span class="Keyword">=</span> __e[i];
|
|
i <span class="Keyword">%</span> <span class="Number">2</span> <span class="Keyword">===</span> <span class="Number">0</span> ? highlight(row) : <span class="BuiltInConstant">null</span>;
|
|
}
|
|
}
|
|
__f;
|
|
</pre><br class='clear' /></div>
|
|
<p>
|
|
If you're not iterating over an actual array, you can use a range to
|
|
specify the start and end of an array comprehension:
|
|
<tt>coundown(i) for i in [10..1].</tt>
|
|
</p>
|
|
|
|
<p id="slice">
|
|
<b class="header">Slicing Arrays with Ranges</b>
|
|
CoffeeScript borrows Ruby's
|
|
<a href="http://ruby-doc.org/core/classes/Range.html">range syntax</a>
|
|
for extracting slices of arrays. With two dots (<tt>3..5</tt>), the range
|
|
is inclusive: the first argument is the index of the first element in
|
|
the slice, and the second is the index of the last one. Three dots signify
|
|
a range that excludes the end.
|
|
</p>
|
|
<div class='code'><pre class="idle">numbers<span class="Keyword">:</span> [<span class="Number">0</span>, <span class="Number">1</span>, <span class="Number">2</span>, <span class="Number">3</span>, <span class="Number">4</span>, <span class="Number">5</span>, <span class="Number">6</span>, <span class="Number">7</span>, <span class="Number">8</span>, <span class="Number">9</span>]
|
|
|
|
three_to_six<span class="Keyword">:</span> numbers[<span class="Number">3</span>..<span class="Number">6</span>]
|
|
|
|
numbers_copy<span class="Keyword">:</span> numbers[<span class="Number">0</span>...numbers.length]
|
|
|
|
</pre><pre class="idle"><span class="Storage">var</span> numbers, numbers_copy, three_to_six;
|
|
numbers <span class="Keyword">=</span> [<span class="Number">0</span>, <span class="Number">1</span>, <span class="Number">2</span>, <span class="Number">3</span>, <span class="Number">4</span>, <span class="Number">5</span>, <span class="Number">6</span>, <span class="Number">7</span>, <span class="Number">8</span>, <span class="Number">9</span>];
|
|
three_to_six <span class="Keyword">=</span> numbers.<span class="LibraryFunction">slice</span>(<span class="Number">3</span>, <span class="Number">6</span> <span class="Keyword">+</span> <span class="Number">1</span>);
|
|
numbers_copy <span class="Keyword">=</span> numbers.<span class="LibraryFunction">slice</span>(<span class="Number">0</span>, numbers.<span class="LibraryConstant">length</span>);
|
|
</pre><button onclick='javascript: var numbers, numbers_copy, three_to_six;
|
|
numbers = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9];
|
|
three_to_six = numbers.slice(3, 6 + 1);
|
|
numbers_copy = numbers.slice(0, numbers.length);
|
|
;alert(numbers_copy);'>run: numbers_copy</button><br class='clear' /></div>
|
|
|
|
<p id="inheritance">
|
|
<b class="header">Inheritance, and Calling Super from a Subclass</b>
|
|
JavaScript's prototypal inheritance has always been a bit of a
|
|
brain-bender, with a whole family tree of libraries that provide a cleaner
|
|
syntax for classical inheritance on top of JavaScript's prototypes:
|
|
<a href="http://code.google.com/p/base2/">Base2</a>,
|
|
<a href="http://prototypejs.org/">Prototype.js</a>,
|
|
<a href="http://jsclass.jcoglan.com/">JS.Class</a>, etc.
|
|
The libraries provide syntactic sugar, but the built-in inheritance would
|
|
be completely usable if it weren't for a couple of small exceptions:
|
|
it's awkward to call <b>super</b> (the prototype object's
|
|
implementation of the current function), and it's awkward to correctly
|
|
set the prototype chain. CoffeeScript provides <tt>extends</tt>
|
|
to help with prototype setup, and converts
|
|
<tt>super()</tt> calls into calls against the immediate ancestor's
|
|
method of the same name.
|
|
</p>
|
|
<div class='code'><pre class="idle"><span class="FunctionName">Animal</span><span class="Keyword">:</span> <span class="Storage">=></span>
|
|
<span class="FunctionName">Animal.prototype.move</span><span class="Keyword">:</span> <span class="FunctionArgument">meters</span> <span class="Storage">=></span>
|
|
alert(<span class="Variable">this</span>.name <span class="Keyword">+</span> <span class="String"><span class="String">"</span> moved <span class="String">"</span></span> <span class="Keyword">+</span> meters <span class="Keyword">+</span> <span class="String"><span class="String">"</span>m.<span class="String">"</span></span>)
|
|
|
|
<span class="FunctionName">Snake</span><span class="Keyword">:</span> <span class="FunctionArgument">name</span> <span class="Storage">=></span> <span class="Variable">this</span>.name<span class="Keyword">:</span> name
|
|
Snake <span class="Variable">extends</span> Animal
|
|
<span class="FunctionName">Snake.prototype.move</span><span class="Keyword">:</span> <span class="Storage">=></span>
|
|
alert(<span class="String"><span class="String">"</span>Slithering...<span class="String">"</span></span>)
|
|
<span class="Variable">super</span>(<span class="Number">5</span>)
|
|
|
|
<span class="FunctionName">Horse</span><span class="Keyword">:</span> <span class="FunctionArgument">name</span> <span class="Storage">=></span> <span class="Variable">this</span>.name<span class="Keyword">:</span> name
|
|
Horse <span class="Variable">extends</span> Animal
|
|
<span class="FunctionName">Horse.prototype.move</span><span class="Keyword">:</span> <span class="Storage">=></span>
|
|
alert(<span class="String"><span class="String">"</span>Galloping...<span class="String">"</span></span>)
|
|
<span class="Variable">super</span>(<span class="Number">45</span>)
|
|
|
|
sam<span class="Keyword">:</span> <span class="Keyword">new</span> <span class="TypeName">Snake</span>(<span class="String"><span class="String">"</span>Sammy the Python<span class="String">"</span></span>)
|
|
tom<span class="Keyword">:</span> <span class="Keyword">new</span> <span class="TypeName">Horse</span>(<span class="String"><span class="String">"</span>Tommy the Palomino<span class="String">"</span></span>)
|
|
|
|
sam.move()
|
|
tom.move()
|
|
|
|
|
|
|
|
|
|
</pre><pre class="idle"><span class="Storage">var</span> Animal, Horse, Snake, sam, tom;
|
|
Animal <span class="Keyword">=</span> <span class="Storage">function</span> <span class="FunctionName">Animal</span>() {
|
|
};
|
|
<span class="LibraryClassType">Animal</span>.<span class="LibraryConstant">prototype</span>.<span class="FunctionName">move</span> = <span class="Storage">function</span> <span class="FunctionName">move</span>(<span class="FunctionArgument">meters</span>) {
|
|
<span class="Keyword">return</span> <span class="LibraryFunction">alert</span>(<span class="Variable">this</span>.<span class="LibraryConstant">name</span> <span class="Keyword">+</span> <span class="String"><span class="String">"</span> moved <span class="String">"</span></span> <span class="Keyword">+</span> meters <span class="Keyword">+</span> <span class="String"><span class="String">"</span>m.<span class="String">"</span></span>);
|
|
};
|
|
Snake <span class="Keyword">=</span> <span class="Storage">function</span> <span class="FunctionName">Snake</span>(<span class="FunctionArgument">name</span>) {
|
|
<span class="Keyword">return</span> (<span class="Variable">this</span>.<span class="LibraryConstant">name</span> <span class="Keyword">=</span> name);
|
|
};
|
|
Snake.__superClass__ <span class="Keyword">=</span> Animal.<span class="LibraryConstant">prototype</span>;
|
|
<span class="LibraryClassType">Snake</span>.<span class="LibraryConstant">prototype</span> = <span class="Keyword">new</span> <span class="TypeName">Animal</span>();
|
|
<span class="LibraryClassType">Snake</span>.<span class="LibraryConstant">prototype</span>.<span class="FunctionName">constructor</span> = Snake;
|
|
<span class="LibraryClassType">Snake</span>.<span class="LibraryConstant">prototype</span>.<span class="FunctionName">move</span> = <span class="Storage">function</span> <span class="FunctionName">move</span>() {
|
|
<span class="LibraryFunction">alert</span>(<span class="String"><span class="String">"</span>Slithering...<span class="String">"</span></span>);
|
|
<span class="Keyword">return</span> Snake.__superClass__.move.<span class="LibraryFunction">call</span>(<span class="Variable">this</span>, <span class="Number">5</span>);
|
|
};
|
|
Horse <span class="Keyword">=</span> <span class="Storage">function</span> <span class="FunctionName">Horse</span>(<span class="FunctionArgument">name</span>) {
|
|
<span class="Keyword">return</span> (<span class="Variable">this</span>.<span class="LibraryConstant">name</span> <span class="Keyword">=</span> name);
|
|
};
|
|
Horse.__superClass__ <span class="Keyword">=</span> Animal.<span class="LibraryConstant">prototype</span>;
|
|
<span class="LibraryClassType">Horse</span>.<span class="LibraryConstant">prototype</span> = <span class="Keyword">new</span> <span class="TypeName">Animal</span>();
|
|
<span class="LibraryClassType">Horse</span>.<span class="LibraryConstant">prototype</span>.<span class="FunctionName">constructor</span> = Horse;
|
|
<span class="LibraryClassType">Horse</span>.<span class="LibraryConstant">prototype</span>.<span class="FunctionName">move</span> = <span class="Storage">function</span> <span class="FunctionName">move</span>() {
|
|
<span class="LibraryFunction">alert</span>(<span class="String"><span class="String">"</span>Galloping...<span class="String">"</span></span>);
|
|
<span class="Keyword">return</span> Horse.__superClass__.move.<span class="LibraryFunction">call</span>(<span class="Variable">this</span>, <span class="Number">45</span>);
|
|
};
|
|
sam <span class="Keyword">=</span> <span class="Keyword">new</span> <span class="TypeName">Snake</span>(<span class="String"><span class="String">"</span>Sammy the Python<span class="String">"</span></span>);
|
|
tom <span class="Keyword">=</span> <span class="Keyword">new</span> <span class="TypeName">Horse</span>(<span class="String"><span class="String">"</span>Tommy the Palomino<span class="String">"</span></span>);
|
|
sam.move();
|
|
tom.move();
|
|
</pre><button onclick='javascript: var Animal, Horse, Snake, sam, tom;
|
|
Animal = function Animal() {
|
|
};
|
|
Animal.prototype.move = function move(meters) {
|
|
return alert(this.name + " moved " + meters + "m.");
|
|
};
|
|
Snake = function Snake(name) {
|
|
return (this.name = name);
|
|
};
|
|
Snake.__superClass__ = Animal.prototype;
|
|
Snake.prototype = new Animal();
|
|
Snake.prototype.constructor = Snake;
|
|
Snake.prototype.move = function move() {
|
|
alert("Slithering...");
|
|
return Snake.__superClass__.move.call(this, 5);
|
|
};
|
|
Horse = function Horse(name) {
|
|
return (this.name = name);
|
|
};
|
|
Horse.__superClass__ = Animal.prototype;
|
|
Horse.prototype = new Animal();
|
|
Horse.prototype.constructor = Horse;
|
|
Horse.prototype.move = function move() {
|
|
alert("Galloping...");
|
|
return Horse.__superClass__.move.call(this, 45);
|
|
};
|
|
sam = new Snake("Sammy the Python");
|
|
tom = new Horse("Tommy the Palomino");
|
|
sam.move();
|
|
tom.move();
|
|
;'>run</button><br class='clear' /></div>
|
|
|
|
<p id="embedded">
|
|
<b class="header">Embedded JavaScript</b>
|
|
If you ever need to interpolate literal JavaScript snippets, you can
|
|
use backticks to pass JavaScript straight through.
|
|
</p>
|
|
<div class='code'><pre class="idle">hi<span class="Keyword">:</span> <span class="String"><span class="String">`</span>function() {</span>
|
|
<span class="String"> return [document.title, "Hello JavaScript"].join(": ");</span>
|
|
<span class="String">}<span class="String">`</span></span>
|
|
|
|
|
|
</pre><pre class="idle"><span class="Storage">var</span> hi;
|
|
<span class="FunctionName">hi</span> = <span class="Storage">function</span>() {
|
|
<span class="Keyword">return</span> [<span class="LibraryClassType">document</span>.<span class="LibraryConstant">title</span>, <span class="String"><span class="String">"</span>Hello JavaScript<span class="String">"</span></span>].<span class="LibraryFunction">join</span>(<span class="String"><span class="String">"</span>: <span class="String">"</span></span>);
|
|
};
|
|
</pre><button onclick='javascript: var hi;
|
|
hi = function() {
|
|
return [document.title, "Hello JavaScript"].join(": ");
|
|
};
|
|
;alert(hi());'>run: hi()</button><br class='clear' /></div>
|
|
|
|
<p id="switch">
|
|
<b class="header">Switch/When/Else</b>
|
|
<b>Switch</b> statements in JavaScript are rather broken. You can only
|
|
do comparisons based on string equality, and need to remember to <b>break</b> at the end of
|
|
every <b>case</b> statement to avoid accidentally falling through to
|
|
the default case. CoffeeScript compiles <b>switch</b> statements into JavaScript if-else chains, allowing you to
|
|
compare any object (via <b>===</b>), preventing fall-through, and resulting
|
|
in a returnable, assignable expression. The format is: <tt>switch</tt> condition,
|
|
<tt>when</tt> clauses, <tt>else</tt> the default case.
|
|
</p>
|
|
<div class='code'><pre class="idle"><span class="Keyword">switch</span> day
|
|
<span class="Keyword">when</span> <span class="String"><span class="String">"</span>Tuesday<span class="String">"</span></span> <span class="Keyword">then</span> eat_breakfast()
|
|
<span class="Keyword">when</span> <span class="String"><span class="String">"</span>Wednesday<span class="String">"</span></span> <span class="Keyword">then</span> go_to_the_park()
|
|
<span class="Keyword">when</span> <span class="String"><span class="String">"</span>Saturday<span class="String">"</span></span>
|
|
<span class="Keyword">if</span> day <span class="Keyword">is</span> bingo_day
|
|
go_to_bingo()
|
|
go_dancing()
|
|
<span class="Keyword">when</span> <span class="String"><span class="String">"</span>Sunday<span class="String">"</span></span> <span class="Keyword">then</span> go_to_church()
|
|
<span class="Keyword">else</span> go_to_work()
|
|
</pre><pre class="idle"><span class="Keyword">if</span> (day <span class="Keyword">===</span> <span class="String"><span class="String">"</span>Tuesday<span class="String">"</span></span>) {
|
|
eat_breakfast();
|
|
} <span class="Keyword">else</span> <span class="Keyword">if</span> (day <span class="Keyword">===</span> <span class="String"><span class="String">"</span>Wednesday<span class="String">"</span></span>) {
|
|
go_to_the_park();
|
|
} <span class="Keyword">else</span> <span class="Keyword">if</span> (day <span class="Keyword">===</span> <span class="String"><span class="String">"</span>Saturday<span class="String">"</span></span>) {
|
|
<span class="Keyword">if</span> (day <span class="Keyword">===</span> bingo_day) {
|
|
go_to_bingo();
|
|
go_dancing();
|
|
}
|
|
} <span class="Keyword">else</span> <span class="Keyword">if</span> (day <span class="Keyword">===</span> <span class="String"><span class="String">"</span>Sunday<span class="String">"</span></span>) {
|
|
go_to_church();
|
|
} <span class="Keyword">else</span> {
|
|
go_to_work();
|
|
}
|
|
</pre><br class='clear' /></div>
|
|
|
|
<p id="try">
|
|
<b class="header">Try/Catch/Finally</b>
|
|
Try/catch statements are just about the same as JavaScript (although
|
|
they work as expressions).
|
|
</p>
|
|
<div class='code'><pre class="idle"><span class="Keyword">try</span>
|
|
all_hell_breaks_loose()
|
|
cats_and_dogs_living_together()
|
|
<span class="Keyword">catch</span> error
|
|
print(error)
|
|
<span class="Keyword">finally</span>
|
|
clean_up()
|
|
</pre><pre class="idle"><span class="Keyword">try</span> {
|
|
all_hell_breaks_loose();
|
|
cats_and_dogs_living_together();
|
|
} <span class="Keyword">catch</span> (error) {
|
|
<span class="LibraryFunction">print</span>(error);
|
|
} <span class="Keyword">finally</span> {
|
|
clean_up();
|
|
}
|
|
</pre><br class='clear' /></div>
|
|
|
|
<p id="try">
|
|
<b class="header">Multiline Strings</b>
|
|
Multiline strings are allowed in CoffeeScript.
|
|
</p>
|
|
<div class='code'><pre class="idle">moby_dick<span class="Keyword">:</span> <span class="String"><span class="String">"</span>Call me Ishmael. Some years ago --</span>
|
|
<span class="String">never mind how long precisely -- having little</span>
|
|
<span class="String">or no money in my purse, and nothing particular</span>
|
|
<span class="String">to interest me on shore, I thought I would sail</span>
|
|
<span class="String">about a little and see the watery part of the</span>
|
|
<span class="String">world...<span class="String">"</span></span>
|
|
|
|
|
|
</pre><pre class="idle"><span class="Storage">var</span> moby_dick;
|
|
moby_dick <span class="Keyword">=</span> <span class="String"><span class="String">"</span>Call me Ishmael. Some years ago -- \</span>
|
|
<span class="String">never mind how long precisely -- having little \</span>
|
|
<span class="String">or no money in my purse, and nothing particular \</span>
|
|
<span class="String">to interest me on shore, I thought I would sail \</span>
|
|
<span class="String">about a little and see the watery part of the \</span>
|
|
<span class="String">world...<span class="String">"</span></span>;
|
|
</pre><button onclick='javascript: var moby_dick;
|
|
moby_dick = "Call me Ishmael. Some years ago -- \
|
|
never mind how long precisely -- having little \
|
|
or no money in my purse, and nothing particular \
|
|
to interest me on shore, I thought I would sail \
|
|
about a little and see the watery part of the \
|
|
world...";
|
|
;alert(moby_dick);'>run: moby_dick</button><br class='clear' /></div>
|
|
|
|
<h2 id="resources">Resources</h2>
|
|
|
|
<ul>
|
|
<li>
|
|
<a href="http://github.com/jashkenas/coffee-script/">Source Code</a><br />
|
|
Use <tt>bin/coffee</tt> to test your changes, or <tt>rake gem:install</tt> to
|
|
create and install a custom version of the gem. If you're hacking on the
|
|
parser, use <tt>rake build:parser</tt> to rebuild it.
|
|
</li>
|
|
<li>
|
|
<a href="http://github.com/jashkenas/coffee-script/issues">Bugs and Feature Requests</a>
|
|
</li>
|
|
</ul>
|
|
|
|
<h2 id="contributing">Contributing</h2>
|
|
|
|
<p>
|
|
Here's a wish list of things that would be wonderful to have in
|
|
CoffeeScript:
|
|
</p>
|
|
|
|
<ul>
|
|
<li>
|
|
A CoffeeScript version of the compiler, perhaps using Alessandro Warth's
|
|
<a href="http://tinlizzie.org/ometa/">OMeta</a>.
|
|
</li>
|
|
<li>
|
|
Test cases for any syntax errors you encounter that you think CoffeeScript
|
|
should be able to compile properly.
|
|
</li>
|
|
<li>
|
|
A tutorial that introduces CoffeeScript from the ground up for folks
|
|
without knowledge of JavaScript.
|
|
</li>
|
|
<li>
|
|
Integration with Processing.js's JavaScript API (this would depend on
|
|
having a JavaScript version of the compiler).
|
|
</li>
|
|
<li>
|
|
A lot of the code generation in <tt>nodes.rb</tt> gets into messy
|
|
string manipulation. Techniques for cleaning this up across the board
|
|
would be appreciated.
|
|
</li>
|
|
</ul>
|
|
|
|
<h2 id="change_log">Change Log</h2>
|
|
|
|
<p>
|
|
<b class="header" style="margin-top: 20px;">0.1.6</b>
|
|
Bugfix for running <tt>coffee --interactive</tt> and <tt>--run</tt>
|
|
from outside of the CoffeeScript directory. Bugfix for nested
|
|
function/if-statements.
|
|
</p>
|
|
|
|
<p>
|
|
<b class="header" style="margin-top: 20px;">0.1.5</b>
|
|
Array slice literals and array comprehensions can now both take Ruby-style
|
|
ranges to specify the start and end. JavaScript variable declaration is
|
|
now pushed up to the top of the scope, making all assignment statements into
|
|
expressions. You can use <tt>\</tt> to escape newlines.
|
|
The <tt>coffee-script</tt> command is now called <tt>coffee</tt>.
|
|
</p>
|
|
|
|
<p>
|
|
<b class="header" style="margin-top: 20px;">0.1.4</b>
|
|
The official CoffeeScript extension is now <tt>.coffee</tt> instead of
|
|
<tt>.cs</tt>, which properly belongs to
|
|
<a href="http://en.wikipedia.org/wiki/C_Sharp_(programming_language)">C#</a>.
|
|
Due to popular demand, you can now also use <tt>=</tt> to assign. Unlike
|
|
JavaScript, <tt>=</tt> can also be used within object literals, interchangeably
|
|
with <tt>:</tt>. Made a grammatical fix for chained function calls
|
|
like <tt>func(1)(2)(3)(4)</tt>. Inheritance and super no longer use
|
|
<tt>__proto__</tt>, so they should be IE-compatible now.
|
|
</p>
|
|
|
|
<p>
|
|
<b class="header" style="margin-top: 20px;">0.1.3</b>
|
|
The <tt>coffee</tt> command now includes <tt>--interactive</tt>,
|
|
which launches an interactive CoffeeScript session, and <tt>--run</tt>,
|
|
which directly compiles and executes a script. Both options depend on a
|
|
working installation of Narwhal.
|
|
The <tt>aint</tt> keyword has been replaced by <tt>isnt</tt>, which goes
|
|
together a little smoother with <tt>is</tt>.
|
|
Quoted strings are now allowed as identifiers within object literals: eg.
|
|
<tt>{"5+5": 10}</tt>.
|
|
All assignment operators now use a colon: <tt>+:</tt>, <tt>-:</tt>,
|
|
<tt>*:</tt>, etc.
|
|
</p>
|
|
|
|
<p>
|
|
<b class="header" style="margin-top: 20px;">0.1.2</b>
|
|
Fixed a bug with calling <tt>super()</tt> through more than one level of
|
|
inheritance, with the re-addition of the <tt>extends</tt> keyword.
|
|
Added experimental <a href="http://narwhaljs.org/">Narwhal</a>
|
|
support (as a Tusk package), contributed by
|
|
<a href="http://tlrobinson.net/">Tom Robinson</a>, including
|
|
<b>bin/cs</b> as a CoffeeScript REPL and interpreter.
|
|
New <tt>--no-wrap</tt> option to suppress the safety function
|
|
wrapper.
|
|
</p>
|
|
|
|
<p>
|
|
<b class="header" style="margin-top: 20px;">0.1.1</b>
|
|
Added <tt>instanceof</tt> and <tt>typeof</tt> as operators.
|
|
</p>
|
|
|
|
<p>
|
|
<b class="header" style="margin-top: 20px;">0.1.0</b>
|
|
Initial CoffeeScript release.
|
|
</p>
|
|
|
|
</div>
|
|
|
|
</body>
|
|
</html>
|