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<!DOCTYPE html> <html> <head> <title>repl.coffee</title> <meta http-equiv="content-type" content="text/html; charset=UTF-8"> <link rel="stylesheet" media="all" href="docco.css" /> </head> <body> <div id="container"> <div id="background"></div> <div id="jump_to"> Jump To &hellip; <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.coffee </a> </div> </div> </div> <table cellpadding="0" cellspacing="0"> <thead> <tr> <th class="docs"> <h1> repl.coffee </h1> </th> <th class="code"> </th> </tr> </thead> <tbody> <tr id="section-1"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-1">&#182;</a> </div> <p>A very simple Read-Eval-Print-Loop. Compiles one line at a time to JavaScript
and evaluates it. Good for simple tests, or poking around the <strong>Node.js</strong> API.
Using it looks like this:</p>
<pre><code>coffee&gt; console.log "#{num} bottles of beer" for num in [99..1]
</code></pre> </td> <td class="code"> <div class="highlight"><pre></pre></div> </td> </tr> <tr id="section-2"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-2">&#182;</a> </div> <p>Require the <strong>coffee-script</strong> module to get access to the compiler.</p> </td> <td class="code"> <div class="highlight"><pre><span class="nv">CoffeeScript = </span><span class="nx">require</span> <span class="s1">&#39;./coffee-script&#39;</span>
<span class="nv">readline = </span><span class="nx">require</span> <span class="s1">&#39;readline&#39;</span>
<span class="p">{</span><span class="nx">inspect</span><span class="p">}</span> <span class="o">=</span> <span class="nx">require</span> <span class="s1">&#39;util&#39;</span>
<span class="p">{</span><span class="nx">Script</span><span class="p">}</span> <span class="o">=</span> <span class="nx">require</span> <span class="s1">&#39;vm&#39;</span>
<span class="nv">Module = </span><span class="nx">require</span> <span class="s1">&#39;module&#39;</span></pre></div> </td> </tr> <tr id="section-3"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-3">&#182;</a> </div> <p>REPL Setup</p> </td> <td class="code"> <div class="highlight"><pre></pre></div> </td> </tr> <tr id="section-4"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-4">&#182;</a> </div> <p>Config</p> </td> <td class="code"> <div class="highlight"><pre><span class="nv">REPL_PROMPT = </span><span class="s1">&#39;coffee&gt; &#39;</span>
<span class="nv">REPL_PROMPT_CONTINUATION = </span><span class="s1">&#39;......&gt; &#39;</span>
<span class="nv">enableColours = </span><span class="kc">no</span>
<span class="nx">unless</span> <span class="nx">process</span><span class="p">.</span><span class="nx">platform</span> <span class="o">is</span> <span class="s1">&#39;win32&#39;</span>
<span class="nv">enableColours = </span><span class="o">not</span> <span class="nx">process</span><span class="p">.</span><span class="nx">env</span><span class="p">.</span><span class="nx">NODE_DISABLE_COLORS</span></pre></div> </td> </tr> <tr id="section-5"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-5">&#182;</a> </div> <p>Start by opening up <code>stdin</code> and <code>stdout</code>.</p> </td> <td class="code"> <div class="highlight"><pre><span class="nv">stdin = </span><span class="nx">process</span><span class="p">.</span><span class="nx">openStdin</span><span class="p">()</span>
<span class="nv">stdout = </span><span class="nx">process</span><span class="p">.</span><span class="nx">stdout</span></pre></div> </td> </tr> <tr id="section-6"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-6">&#182;</a> </div> <p>Log an error.</p> </td> <td class="code"> <div class="highlight"><pre><span class="nv">error = </span><span class="p">(</span><span class="nx">err</span><span class="p">)</span> <span class="o">-&gt;</span>
<span class="nx">stdout</span><span class="p">.</span><span class="nx">write</span> <span class="p">(</span><span class="nx">err</span><span class="p">.</span><span class="nx">stack</span> <span class="o">or</span> <span class="nx">err</span><span class="p">.</span><span class="nx">toString</span><span class="p">())</span> <span class="o">+</span> <span class="s1">&#39;\n\n&#39;</span></pre></div> </td> </tr> <tr id="section-7"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-7">&#182;</a> </div> <p>The current backlog of multi-line code.</p> </td> <td class="code"> <div class="highlight"><pre><span class="nv">backlog = </span><span class="s1">&#39;&#39;</span></pre></div> </td> </tr> <tr id="section-8"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-8">&#182;</a> </div> <p>The REPL context; must be visible outside <code>run</code> to allow for tab completion</p> </td> <td class="code"> <div class="highlight"><pre><span class="nv">sandbox = </span><span class="nx">Script</span><span class="p">.</span><span class="nx">createContext</span><span class="p">()</span>
<span class="nv">nonContextGlobals = </span><span class="p">[</span>
<span class="s1">&#39;Buffer&#39;</span><span class="p">,</span> <span class="s1">&#39;console&#39;</span><span class="p">,</span> <span class="s1">&#39;process&#39;</span>
<span class="s1">&#39;setInterval&#39;</span><span class="p">,</span> <span class="s1">&#39;clearInterval&#39;</span>
<span class="s1">&#39;setTimeout&#39;</span><span class="p">,</span> <span class="s1">&#39;clearTimeout&#39;</span>
<span class="p">]</span>
<span class="nx">sandbox</span><span class="p">[</span><span class="nx">g</span><span class="p">]</span> <span class="o">=</span> <span class="nx">global</span><span class="p">[</span><span class="nx">g</span><span class="p">]</span> <span class="k">for</span> <span class="nx">g</span> <span class="k">in</span> <span class="nx">nonContextGlobals</span>
<span class="nv">sandbox.global = sandbox.root = sandbox.GLOBAL = </span><span class="nx">sandbox</span></pre></div> </td> </tr> <tr id="section-9"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-9">&#182;</a> </div> <p>The main REPL function. <strong>run</strong> is called every time a line of code is entered.
Attempt to evaluate the command. If there's an exception, print it out instead
of exiting.</p> </td> <td class="code"> <div class="highlight"><pre><span class="nv">run = </span><span class="p">(</span><span class="nx">buffer</span><span class="p">)</span> <span class="o">-&gt;</span>
<span class="k">if</span> <span class="o">!</span><span class="nx">buffer</span><span class="p">.</span><span class="nx">toString</span><span class="p">().</span><span class="nx">trim</span><span class="p">()</span> <span class="o">and</span> <span class="o">!</span><span class="nx">backlog</span>
<span class="nx">repl</span><span class="p">.</span><span class="nx">prompt</span><span class="p">()</span>
<span class="k">return</span>
<span class="nv">code = </span><span class="nx">backlog</span> <span class="o">+=</span> <span class="nx">buffer</span>
<span class="k">if</span> <span class="nx">code</span><span class="p">[</span><span class="nx">code</span><span class="p">.</span><span class="nx">length</span> <span class="o">-</span> <span class="mi">1</span><span class="p">]</span> <span class="o">is</span> <span class="s1">&#39;\\&#39;</span>
<span class="nv">backlog = </span><span class="s2">&quot;#{backlog[...-1]}\n&quot;</span>
<span class="nx">repl</span><span class="p">.</span><span class="nx">setPrompt</span> <span class="nx">REPL_PROMPT_CONTINUATION</span>
<span class="nx">repl</span><span class="p">.</span><span class="nx">prompt</span><span class="p">()</span>
<span class="k">return</span>
<span class="nx">repl</span><span class="p">.</span><span class="nx">setPrompt</span> <span class="nx">REPL_PROMPT</span>
<span class="nv">backlog = </span><span class="s1">&#39;&#39;</span>
<span class="k">try</span>
<span class="nv">_ = </span><span class="nx">sandbox</span><span class="p">.</span><span class="nx">_</span>
<span class="nv">returnValue = </span><span class="nx">CoffeeScript</span><span class="p">.</span><span class="nb">eval</span> <span class="s2">&quot;_=(#{code}\n)&quot;</span><span class="p">,</span> <span class="p">{</span>
<span class="nx">sandbox</span><span class="p">,</span>
<span class="nx">filename</span><span class="o">:</span> <span class="s1">&#39;repl&#39;</span>
<span class="nx">modulename</span><span class="o">:</span> <span class="s1">&#39;repl&#39;</span>
<span class="p">}</span>
<span class="k">if</span> <span class="nx">returnValue</span> <span class="o">is</span> <span class="kc">undefined</span>
<span class="nv">sandbox._ = </span><span class="nx">_</span>
<span class="k">else</span>
<span class="nx">process</span><span class="p">.</span><span class="nx">stdout</span><span class="p">.</span><span class="nx">write</span> <span class="nx">inspect</span><span class="p">(</span><span class="nx">returnValue</span><span class="p">,</span> <span class="kc">no</span><span class="p">,</span> <span class="mi">2</span><span class="p">,</span> <span class="nx">enableColours</span><span class="p">)</span> <span class="o">+</span> <span class="s1">&#39;\n&#39;</span>
<span class="k">catch</span> <span class="nx">err</span>
<span class="nx">error</span> <span class="nx">err</span>
<span class="nx">repl</span><span class="p">.</span><span class="nx">prompt</span><span class="p">()</span></pre></div> </td> </tr> <tr id="section-10"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-10">&#182;</a> </div> <h1>Autocompletion</h1> </td> <td class="code"> <div class="highlight"><pre></pre></div> </td> </tr> <tr id="section-11"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-11">&#182;</a> </div> <p>Regexes to match complete-able bits of text.</p> </td> <td class="code"> <div class="highlight"><pre><span class="nv">ACCESSOR = </span><span class="sr">/\s*([\w\.]+)(?:\.(\w*))$/</span>
<span class="nv">SIMPLEVAR = </span><span class="sr">/\s*(\w*)$/i</span></pre></div> </td> </tr> <tr id="section-12"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-12">&#182;</a> </div> <p>Returns a list of completions, and the completed text.</p> </td> <td class="code"> <div class="highlight"><pre><span class="nv">autocomplete = </span><span class="p">(</span><span class="nx">text</span><span class="p">)</span> <span class="o">-&gt;</span>
<span class="nx">completeAttribute</span><span class="p">(</span><span class="nx">text</span><span class="p">)</span> <span class="o">or</span> <span class="nx">completeVariable</span><span class="p">(</span><span class="nx">text</span><span class="p">)</span> <span class="o">or</span> <span class="p">[[],</span> <span class="nx">text</span><span class="p">]</span></pre></div> </td> </tr> <tr id="section-13"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-13">&#182;</a> </div> <p>Attempt to autocomplete a chained dotted attribute: <code>one.two.three</code>.</p> </td> <td class="code"> <div class="highlight"><pre><span class="nv">completeAttribute = </span><span class="p">(</span><span class="nx">text</span><span class="p">)</span> <span class="o">-&gt;</span>
<span class="k">if</span> <span class="nv">match = </span><span class="nx">text</span><span class="p">.</span><span class="nx">match</span> <span class="nx">ACCESSOR</span>
<span class="p">[</span><span class="nx">all</span><span class="p">,</span> <span class="nx">obj</span><span class="p">,</span> <span class="nx">prefix</span><span class="p">]</span> <span class="o">=</span> <span class="nx">match</span>
<span class="k">try</span>
<span class="nv">val = </span><span class="nx">Script</span><span class="p">.</span><span class="nx">runInContext</span> <span class="nx">obj</span><span class="p">,</span> <span class="nx">sandbox</span>
<span class="k">catch</span> <span class="nx">error</span>
<span class="k">return</span>
<span class="nv">completions = </span><span class="nx">getCompletions</span> <span class="nx">prefix</span><span class="p">,</span> <span class="nb">Object</span><span class="p">.</span><span class="nx">getOwnPropertyNames</span> <span class="nx">val</span>
<span class="p">[</span><span class="nx">completions</span><span class="p">,</span> <span class="nx">prefix</span><span class="p">]</span></pre></div> </td> </tr> <tr id="section-14"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-14">&#182;</a> </div> <p>Attempt to autocomplete an in-scope free variable: <code>one</code>.</p> </td> <td class="code"> <div class="highlight"><pre><span class="nv">completeVariable = </span><span class="p">(</span><span class="nx">text</span><span class="p">)</span> <span class="o">-&gt;</span>
<span class="k">if</span> <span class="nv">free = </span><span class="p">(</span><span class="nx">text</span><span class="p">.</span><span class="nx">match</span> <span class="nx">SIMPLEVAR</span><span class="p">)</span><span class="o">?</span><span class="p">[</span><span class="mi">1</span><span class="p">]</span>
<span class="nv">vars = </span><span class="nx">Script</span><span class="p">.</span><span class="nx">runInContext</span> <span class="s1">&#39;Object.getOwnPropertyNames(this)&#39;</span><span class="p">,</span> <span class="nx">sandbox</span>
<span class="nv">possibilities = </span><span class="nx">vars</span><span class="p">.</span><span class="nx">concat</span> <span class="nx">CoffeeScript</span><span class="p">.</span><span class="nx">RESERVED</span>
<span class="nv">completions = </span><span class="nx">getCompletions</span> <span class="nx">free</span><span class="p">,</span> <span class="nx">possibilities</span>
<span class="p">[</span><span class="nx">completions</span><span class="p">,</span> <span class="nx">free</span><span class="p">]</span></pre></div> </td> </tr> <tr id="section-15"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-15">&#182;</a> </div> <p>Return elements of candidates for which <code>prefix</code> is a prefix.</p> </td> <td class="code"> <div class="highlight"><pre><span class="nv">getCompletions = </span><span class="p">(</span><span class="nx">prefix</span><span class="p">,</span> <span class="nx">candidates</span><span class="p">)</span> <span class="o">-&gt;</span>
<span class="p">(</span><span class="nx">el</span> <span class="k">for</span> <span class="nx">el</span> <span class="k">in</span> <span class="nx">candidates</span> <span class="k">when</span> <span class="nx">el</span><span class="p">.</span><span class="nx">indexOf</span><span class="p">(</span><span class="nx">prefix</span><span class="p">)</span> <span class="o">is</span> <span class="mi">0</span><span class="p">)</span></pre></div> </td> </tr> <tr id="section-16"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-16">&#182;</a> </div> <p>Make sure that uncaught exceptions don't kill the REPL.</p> </td> <td class="code"> <div class="highlight"><pre><span class="nx">process</span><span class="p">.</span><span class="kc">on</span> <span class="s1">&#39;uncaughtException&#39;</span><span class="p">,</span> <span class="nx">error</span></pre></div> </td> </tr> <tr id="section-17"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-17">&#182;</a> </div> <p>Create the REPL by listening to <strong>stdin</strong>.</p> </td> <td class="code"> <div class="highlight"><pre><span class="k">if</span> <span class="nx">readline</span><span class="p">.</span><span class="nx">createInterface</span><span class="p">.</span><span class="nx">length</span> <span class="o">&lt;</span> <span class="mi">3</span>
<span class="nv">repl = </span><span class="nx">readline</span><span class="p">.</span><span class="nx">createInterface</span> <span class="nx">stdin</span><span class="p">,</span> <span class="nx">autocomplete</span>
<span class="nx">stdin</span><span class="p">.</span><span class="kc">on</span> <span class="s1">&#39;data&#39;</span><span class="p">,</span> <span class="p">(</span><span class="nx">buffer</span><span class="p">)</span> <span class="o">-&gt;</span> <span class="nx">repl</span><span class="p">.</span><span class="nx">write</span> <span class="nx">buffer</span>
<span class="k">else</span>
<span class="nv">repl = </span><span class="nx">readline</span><span class="p">.</span><span class="nx">createInterface</span> <span class="nx">stdin</span><span class="p">,</span> <span class="nx">stdout</span><span class="p">,</span> <span class="nx">autocomplete</span>
<span class="nx">repl</span><span class="p">.</span><span class="kc">on</span> <span class="s1">&#39;attemptClose&#39;</span><span class="p">,</span> <span class="o">-&gt;</span>
<span class="k">if</span> <span class="nx">backlog</span>
<span class="nv">backlog = </span><span class="s1">&#39;&#39;</span>
<span class="nx">process</span><span class="p">.</span><span class="nx">stdout</span><span class="p">.</span><span class="nx">write</span> <span class="s1">&#39;\n&#39;</span>
<span class="nx">repl</span><span class="p">.</span><span class="nx">setPrompt</span> <span class="nx">REPL_PROMPT</span>
<span class="nx">repl</span><span class="p">.</span><span class="nx">prompt</span><span class="p">()</span>
<span class="k">else</span>
<span class="nx">repl</span><span class="p">.</span><span class="nx">close</span><span class="p">()</span>
<span class="nx">repl</span><span class="p">.</span><span class="kc">on</span> <span class="s1">&#39;close&#39;</span><span class="p">,</span> <span class="o">-&gt;</span>
<span class="nx">process</span><span class="p">.</span><span class="nx">stdout</span><span class="p">.</span><span class="nx">write</span> <span class="s1">&#39;\n&#39;</span>
<span class="nx">stdin</span><span class="p">.</span><span class="nx">destroy</span><span class="p">()</span>
<span class="nx">repl</span><span class="p">.</span><span class="kc">on</span> <span class="s1">&#39;line&#39;</span><span class="p">,</span> <span class="nx">run</span>
<span class="nx">repl</span><span class="p">.</span><span class="nx">setPrompt</span> <span class="nx">REPL_PROMPT</span>
<span class="nx">repl</span><span class="p">.</span><span class="nx">prompt</span><span class="p">()</span>
</pre></div> </td> </tr> </tbody> </table> </div> </body> </html>