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<!DOCTYPE html> <html> <head> <title>nodes.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 … <div id="jump_wrapper"> <div id="jump_page"> <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> nodes.coffee </h1> </th> <th class="code"> </th> </tr> </thead> <tbody> <tr id="section-1"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-1">#</a> </div> <p><code>nodes.coffee</code> contains all of the node classes for the syntax tree. Most
nodes are created as the result of actions in the <a href="grammar.html">grammar</a>,
but some are created by other nodes as a method of code generation. To convert
the syntax tree into a string of JavaScript code, call <code>compile()</code> on the root.</p> </td> <td class="code"> <div class="highlight"><pre></pre></div> </td> </tr> <tr id="section-2"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-2">#</a> </div> <p>Set up for both <strong>Node.js</strong> and the browser, by
including the <a href="scope.html">Scope</a> class and the <a href="helpers.html">helper</a> functions.</p> </td> <td class="code"> <div class="highlight"><pre><span class="k">if</span> <span class="nx">process</span><span class="o">?</span>
<span class="nv">Scope: </span> <span class="nx">require</span><span class="p">(</span><span class="s1">'./scope'</span><span class="p">).</span><span class="nx">Scope</span>
<span class="nv">helpers: </span><span class="nx">require</span><span class="p">(</span><span class="s1">'./helpers'</span><span class="p">).</span><span class="nx">helpers</span>
<span class="k">else</span>
<span class="k">this</span><span class="p">.</span><span class="nv">exports: </span><span class="k">this</span>
<span class="nv">helpers: </span> <span class="k">this</span><span class="p">.</span><span class="nx">helpers</span>
<span class="nv">Scope: </span> <span class="k">this</span><span class="p">.</span><span class="nx">Scope</span></pre></div> </td> </tr> <tr id="section-3"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-3">#</a> </div> <p>Import the helpers we plan to use.</p> </td> <td class="code"> <div class="highlight"><pre><span class="p">{</span><span class="nx">compact</span><span class="p">,</span> <span class="nx">flatten</span><span class="p">,</span> <span class="nx">merge</span><span class="p">,</span> <span class="nx">del</span><span class="p">,</span> <span class="nx">index_of</span><span class="p">}</span><span class="o">:</span> <span class="nx">helpers</span></pre></div> </td> </tr> <tr id="section-4"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-4">#</a> </div> <p>Helper function that marks a node as a JavaScript <em>statement</em>, or as a
<em>pure_statement</em>. Statements must be wrapped in a closure when used as an
expression, and nodes tagged as <em>pure_statement</em> cannot be closure-wrapped
without losing their meaning.</p> </td> <td class="code"> <div class="highlight"><pre><span class="nv">statement: </span><span class="p">(</span><span class="nx">klass</span><span class="p">,</span> <span class="nx">only</span><span class="p">)</span> <span class="o">-></span>
<span class="nv">klass::is_statement: </span><span class="o">-></span> <span class="kc">true</span>
<span class="p">(</span><span class="nv">klass::is_pure_statement: </span><span class="o">-></span> <span class="kc">true</span><span class="p">)</span> <span class="k">if</span> <span class="nx">only</span>
<span class="nv">children: </span><span class="p">(</span><span class="nx">klass</span><span class="p">,</span> <span class="nx">child_attrs</span><span class="p">...)</span> <span class="o">-></span>
<span class="nv">klass::children_attributes: </span><span class="nx">child_attrs</span></pre></div> </td> </tr> <tr id="section-5"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-5">#</a> </div> <h3>BaseNode</h3> </td> <td class="code"> <div class="highlight"><pre></pre></div> </td> </tr> <tr id="section-6"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-6">#</a> </div> <p>The <strong>BaseNode</strong> is the abstract base class for all nodes in the syntax tree.
Each subclass implements the <code>compile_node</code> method, which performs the
code generation for that node. To compile a node to JavaScript,
call <code>compile</code> on it, which wraps <code>compile_node</code> in some generic extra smarts,
to know when the generated code needs to be wrapped up in a closure.
An options hash is passed and cloned throughout, containing information about
the environment from higher in the tree (such as if a returned value is
being requested by the surrounding function), information about the current
scope, and indentation level.</p> </td> <td class="code"> <div class="highlight"><pre><span class="nv">exports.BaseNode: </span><span class="nx">class</span> <span class="nx">BaseNode</span></pre></div> </td> </tr> <tr id="section-7"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-7">#</a> </div> <p>Common logic for determining whether to wrap this node in a closure before
compiling it, or to compile directly. We need to wrap if this node is a
<em>statement</em>, and it's not a <em>pure_statement</em>, and we're not at
the top level of a block (which would be unnecessary), and we haven't
already been asked to return the result (because statements know how to
return results).</p>
<p>If a Node is <em>top_sensitive</em>, that means that it needs to compile differently
depending on whether it's being used as part of a larger expression, or is a
top-level statement within the function body.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nv">compile: </span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="o">-></span>
<span class="vi">@options: </span><span class="nx">merge</span> <span class="nx">o</span> <span class="o">or</span> <span class="p">{}</span>
<span class="vi">@tab: </span> <span class="nx">o</span><span class="p">.</span><span class="nx">indent</span>
<span class="nx">unless</span> <span class="k">this</span> <span class="k">instanceof</span> <span class="nx">ValueNode</span> <span class="o">or</span> <span class="k">this</span> <span class="k">instanceof</span> <span class="nx">CallNode</span>
<span class="nx">del</span> <span class="nx">@options</span><span class="p">,</span> <span class="s1">'operation'</span>
<span class="nx">del</span> <span class="nx">@options</span><span class="p">,</span> <span class="s1">'chain_root'</span> <span class="nx">unless</span> <span class="k">this</span> <span class="k">instanceof</span> <span class="nx">AccessorNode</span> <span class="o">or</span> <span class="k">this</span> <span class="k">instanceof</span> <span class="nx">IndexNode</span>
<span class="nv">top: </span> <span class="k">if</span> <span class="nx">@top_sensitive</span><span class="p">()</span> <span class="k">then</span> <span class="nx">@options</span><span class="p">.</span><span class="nx">top</span> <span class="k">else</span> <span class="nx">del</span> <span class="nx">@options</span><span class="p">,</span> <span class="s1">'top'</span>
<span class="nv">closure: </span> <span class="nx">@is_statement</span><span class="p">()</span> <span class="o">and</span> <span class="o">not</span> <span class="nx">@is_pure_statement</span><span class="p">()</span> <span class="o">and</span> <span class="o">not</span> <span class="nx">top</span> <span class="o">and</span>
<span class="o">not</span> <span class="nx">@options</span><span class="p">.</span><span class="nx">as_statement</span> <span class="o">and</span> <span class="o">not</span> <span class="p">(</span><span class="k">this</span> <span class="k">instanceof</span> <span class="nx">CommentNode</span><span class="p">)</span> <span class="o">and</span>
<span class="o">not</span> <span class="nx">@contains_pure_statement</span><span class="p">()</span>
<span class="k">if</span> <span class="nx">closure</span> <span class="k">then</span> <span class="nx">@compile_closure</span><span class="p">(</span><span class="nx">@options</span><span class="p">)</span> <span class="k">else</span> <span class="nx">@compile_node</span><span class="p">(</span><span class="nx">@options</span><span class="p">)</span></pre></div> </td> </tr> <tr id="section-8"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-8">#</a> </div> <p>Statements converted into expressions via closure-wrapping share a scope
object with their parent closure, to preserve the expected lexical scope.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nv">compile_closure: </span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="o">-></span>
<span class="vi">@tab: </span><span class="nx">o</span><span class="p">.</span><span class="nx">indent</span>
<span class="nv">o.shared_scope: </span><span class="nx">o</span><span class="p">.</span><span class="nx">scope</span>
<span class="nx">ClosureNode</span><span class="p">.</span><span class="nx">wrap</span><span class="p">(</span><span class="k">this</span><span class="p">).</span><span class="nx">compile</span> <span class="nx">o</span></pre></div> </td> </tr> <tr id="section-9"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-9">#</a> </div> <p>If the code generation wishes to use the result of a complex expression
in multiple places, ensure that the expression is only ever evaluated once,
by assigning it to a temporary variable.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nv">compile_reference: </span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="o">-></span>
<span class="nv">reference: </span><span class="nx">literal</span> <span class="nx">o</span><span class="p">.</span><span class="nx">scope</span><span class="p">.</span><span class="nx">free_variable</span><span class="p">()</span>
<span class="nv">compiled: </span> <span class="k">new</span> <span class="nx">AssignNode</span> <span class="nx">reference</span><span class="p">,</span> <span class="k">this</span>
<span class="p">[</span><span class="nx">compiled</span><span class="p">,</span> <span class="nx">reference</span><span class="p">]</span></pre></div> </td> </tr> <tr id="section-10"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-10">#</a> </div> <p>Convenience method to grab the current indentation level, plus tabbing in.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nv">idt: </span><span class="p">(</span><span class="nx">tabs</span><span class="p">)</span> <span class="o">-></span>
<span class="nv">idt: </span><span class="nx">@tab</span> <span class="o">or</span> <span class="s1">''</span>
<span class="nv">num: </span><span class="p">(</span><span class="nx">tabs</span> <span class="o">or</span> <span class="mi">0</span><span class="p">)</span> <span class="o">+</span> <span class="mi">1</span>
<span class="nv">idt: </span><span class="o">+</span> <span class="nx">TAB</span> <span class="k">while</span> <span class="nv">num: </span><span class="o">-</span> <span class="mi">1</span>
<span class="nx">idt</span></pre></div> </td> </tr> <tr id="section-11"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-11">#</a> </div> <p>Construct a node that returns the current node's result.
Note that this is overridden for smarter behavior for
many statement nodes (eg IfNode, ForNode)...</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nv">make_return: </span><span class="o">-></span>
<span class="k">new</span> <span class="nx">ReturnNode</span> <span class="k">this</span></pre></div> </td> </tr> <tr id="section-12"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-12">#</a> </div> <p>Does this node, or any of its children, contain a node of a certain kind?
Recursively traverses down the <em>children</em> of the nodes, yielding to a block
and returning true when the block finds a match. <code>contains</code> does not cross
scope boundaries.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nv">contains: </span><span class="p">(</span><span class="nx">block</span><span class="p">)</span> <span class="o">-></span>
<span class="nv">contains: </span><span class="kc">false</span>
<span class="nx">@traverse_children</span> <span class="kc">false</span><span class="p">,</span> <span class="p">(</span><span class="nx">node</span><span class="p">)</span> <span class="o">-></span>
<span class="k">if</span> <span class="nx">block</span><span class="p">(</span><span class="nx">node</span><span class="p">)</span>
<span class="nv">contains: </span><span class="kc">true</span>
<span class="k">return</span> <span class="kc">false</span>
<span class="nx">contains</span></pre></div> </td> </tr> <tr id="section-13"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-13">#</a> </div> <p>Is this node of a certain type, or does it contain the type?</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nv">contains_type: </span><span class="p">(</span><span class="nx">type</span><span class="p">)</span> <span class="o">-></span>
<span class="k">this</span> <span class="k">instanceof</span> <span class="nx">type</span> <span class="o">or</span> <span class="nx">@contains</span> <span class="p">(</span><span class="nx">n</span><span class="p">)</span> <span class="o">-></span> <span class="nx">n</span> <span class="k">instanceof</span> <span class="nx">type</span></pre></div> </td> </tr> <tr id="section-14"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-14">#</a> </div> <p>Convenience for the most common use of contains. Does the node contain
a pure statement?</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nv">contains_pure_statement: </span><span class="o">-></span>
<span class="nx">@is_pure_statement</span><span class="p">()</span> <span class="o">or</span> <span class="nx">@contains</span> <span class="p">(</span><span class="nx">n</span><span class="p">)</span> <span class="o">-></span> <span class="nx">n</span><span class="p">.</span><span class="nx">is_pure_statement</span><span class="p">()</span></pre></div> </td> </tr> <tr id="section-15"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-15">#</a> </div> <p>Perform an in-order traversal of the AST. Crosses scope boundaries.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nv">traverse: </span><span class="p">(</span><span class="nx">block</span><span class="p">)</span> <span class="o">-></span> <span class="nx">@traverse_children</span> <span class="kc">true</span><span class="p">,</span> <span class="nx">block</span></pre></div> </td> </tr> <tr id="section-16"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-16">#</a> </div> <p><code>toString</code> representation of the node, for inspecting the parse tree.
This is what <code>coffee --nodes</code> prints out.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nv">toString: </span><span class="p">(</span><span class="nx">idt</span><span class="p">)</span> <span class="o">-></span>
<span class="nv">idt: </span><span class="o">or</span> <span class="s1">''</span>
<span class="s1">'\n'</span> <span class="o">+</span> <span class="nx">idt</span> <span class="o">+</span> <span class="nx">@constructor</span><span class="p">.</span><span class="nx">name</span> <span class="o">+</span> <span class="p">(</span><span class="nx">child</span><span class="p">.</span><span class="nx">toString</span><span class="p">(</span><span class="nx">idt</span> <span class="o">+</span> <span class="nx">TAB</span><span class="p">)</span> <span class="k">for</span> <span class="nx">child</span> <span class="k">in</span> <span class="nx">@children</span><span class="p">()).</span><span class="nx">join</span><span class="p">(</span><span class="s1">''</span><span class="p">)</span>
<span class="nv">children: </span><span class="o">-></span>
<span class="nv">nodes: </span><span class="p">[]</span>
<span class="nx">@each_child</span> <span class="p">(</span><span class="nx">node</span><span class="p">)</span> <span class="o">-></span> <span class="nx">nodes</span><span class="p">.</span><span class="nx">push</span> <span class="nx">node</span>
<span class="nx">nodes</span>
<span class="nv">each_child: </span><span class="p">(</span><span class="nx">func</span><span class="p">)</span> <span class="o">-></span>
<span class="k">for</span> <span class="nx">attr</span> <span class="k">in</span> <span class="nx">@children_attributes</span> <span class="k">when</span> <span class="k">this</span><span class="p">[</span><span class="nx">attr</span><span class="p">]</span>
<span class="k">for</span> <span class="nx">child</span> <span class="k">in</span> <span class="nx">flatten</span> <span class="p">[</span><span class="k">this</span><span class="p">[</span><span class="nx">attr</span><span class="p">]]</span>
<span class="k">return</span> <span class="k">if</span> <span class="nx">func</span><span class="p">(</span><span class="nx">child</span><span class="p">)</span> <span class="o">is</span> <span class="kc">false</span>
<span class="nv">traverse_children: </span><span class="p">(</span><span class="nx">cross_scope</span><span class="p">,</span> <span class="nx">func</span><span class="p">)</span> <span class="o">-></span>
<span class="k">return</span> <span class="nx">unless</span> <span class="nx">@children_attributes</span>
<span class="nx">@each_child</span> <span class="p">(</span><span class="nx">child</span><span class="p">)</span> <span class="o">-></span>
<span class="nx">func</span><span class="p">.</span><span class="nx">apply</span><span class="p">(</span><span class="k">this</span><span class="p">,</span> <span class="nx">arguments</span><span class="p">)</span>
<span class="nx">child</span><span class="p">.</span><span class="nx">traverse_children</span><span class="p">(</span><span class="nx">cross_scope</span><span class="p">,</span> <span class="nx">func</span><span class="p">)</span> <span class="k">if</span> <span class="nx">child</span> <span class="k">instanceof</span> <span class="nx">BaseNode</span></pre></div> </td> </tr> <tr id="section-17"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-17">#</a> </div> <p>Default implementations of the common node identification methods. Nodes
will override these with custom logic, if needed.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nv">unwrap: </span> <span class="o">-></span> <span class="k">this</span>
<span class="nv">is_statement: </span> <span class="o">-></span> <span class="kc">false</span>
<span class="nv">is_pure_statement: </span> <span class="o">-></span> <span class="kc">false</span>
<span class="nv">top_sensitive: </span> <span class="o">-></span> <span class="kc">false</span></pre></div> </td> </tr> <tr id="section-18"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-18">#</a> </div> <h3>Expressions</h3> </td> <td class="code"> <div class="highlight"><pre></pre></div> </td> </tr> <tr id="section-19"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-19">#</a> </div> <p>The expressions body is the list of expressions that forms the body of an
indented block of code -- the implementation of a function, a clause in an
<code>if</code>, <code>switch</code>, or <code>try</code>, and so on...</p> </td> <td class="code"> <div class="highlight"><pre><span class="nv">exports.Expressions: </span><span class="nx">class</span> <span class="nx">Expressions</span> <span class="k">extends</span> <span class="nx">BaseNode</span>
<span class="nv">constructor: </span><span class="p">(</span><span class="nx">nodes</span><span class="p">)</span> <span class="o">-></span>
<span class="vi">@expressions: </span><span class="nx">compact</span> <span class="nx">flatten</span> <span class="nx">nodes</span> <span class="o">or</span> <span class="p">[]</span></pre></div> </td> </tr> <tr id="section-20"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-20">#</a> </div> <p>Tack an expression on to the end of this expression list.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nv">push: </span><span class="p">(</span><span class="nx">node</span><span class="p">)</span> <span class="o">-></span>
<span class="nx">@expressions</span><span class="p">.</span><span class="nx">push</span><span class="p">(</span><span class="nx">node</span><span class="p">)</span>
<span class="k">this</span></pre></div> </td> </tr> <tr id="section-21"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-21">#</a> </div> <p>Add an expression at the beginning of this expression list.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nv">unshift: </span><span class="p">(</span><span class="nx">node</span><span class="p">)</span> <span class="o">-></span>
<span class="nx">@expressions</span><span class="p">.</span><span class="nx">unshift</span><span class="p">(</span><span class="nx">node</span><span class="p">)</span>
<span class="k">this</span></pre></div> </td> </tr> <tr id="section-22"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-22">#</a> </div> <p>If this Expressions consists of just a single node, unwrap it by pulling
it back out.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nv">unwrap: </span><span class="o">-></span>
<span class="k">if</span> <span class="nx">@expressions</span><span class="p">.</span><span class="nx">length</span> <span class="o">is</span> <span class="mi">1</span> <span class="k">then</span> <span class="nx">@expressions</span><span class="p">[</span><span class="mi">0</span><span class="p">]</span> <span class="k">else</span> <span class="k">this</span></pre></div> </td> </tr> <tr id="section-23"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-23">#</a> </div> <p>Is this an empty block of code?</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nv">empty: </span><span class="o">-></span>
<span class="nx">@expressions</span><span class="p">.</span><span class="nx">length</span> <span class="o">is</span> <span class="mi">0</span></pre></div> </td> </tr> <tr id="section-24"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-24">#</a> </div> <p>An Expressions node does not return its entire body, rather it
ensures that the final expression is returned.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nv">make_return: </span><span class="o">-></span>
<span class="nv">idx: </span> <span class="nx">@expressions</span><span class="p">.</span><span class="nx">length</span> <span class="o">-</span> <span class="mi">1</span>
<span class="nv">last: </span><span class="nx">@expressions</span><span class="p">[</span><span class="nx">idx</span><span class="p">]</span>
<span class="nv">last: </span><span class="nx">@expressions</span><span class="p">[</span><span class="nv">idx: </span><span class="o">-</span> <span class="mi">1</span><span class="p">]</span> <span class="k">if</span> <span class="nx">last</span> <span class="k">instanceof</span> <span class="nx">CommentNode</span>
<span class="k">return</span> <span class="k">this</span> <span class="k">if</span> <span class="o">not</span> <span class="nx">last</span> <span class="o">or</span> <span class="nx">last</span> <span class="k">instanceof</span> <span class="nx">ReturnNode</span>
<span class="nx">@expressions</span><span class="p">[</span><span class="nx">idx</span><span class="p">]</span><span class="o">:</span> <span class="nx">last</span><span class="p">.</span><span class="nx">make_return</span><span class="p">()</span> <span class="nx">unless</span> <span class="nx">last</span><span class="p">.</span><span class="nx">contains_pure_statement</span><span class="p">()</span>
<span class="k">this</span></pre></div> </td> </tr> <tr id="section-25"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-25">#</a> </div> <p>An <strong>Expressions</strong> is the only node that can serve as the root.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nv">compile: </span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="o">-></span>
<span class="nv">o: </span><span class="o">or</span> <span class="p">{}</span>
<span class="k">if</span> <span class="nx">o</span><span class="p">.</span><span class="nx">scope</span> <span class="k">then</span> <span class="k">super</span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="k">else</span> <span class="nx">@compile_root</span><span class="p">(</span><span class="nx">o</span><span class="p">)</span>
<span class="nv">compile_node: </span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="o">-></span>
<span class="p">(</span><span class="nx">@compile_expression</span><span class="p">(</span><span class="nx">node</span><span class="p">,</span> <span class="nx">merge</span><span class="p">(</span><span class="nx">o</span><span class="p">))</span> <span class="k">for</span> <span class="nx">node</span> <span class="k">in</span> <span class="nx">@expressions</span><span class="p">).</span><span class="nx">join</span><span class="p">(</span><span class="s2">"\n"</span><span class="p">)</span></pre></div> </td> </tr> <tr id="section-26"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-26">#</a> </div> <p>If we happen to be the top-level <strong>Expressions</strong>, wrap everything in
a safety closure, unless requested not to.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nv">compile_root: </span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="o">-></span>
<span class="nv">o.indent: </span><span class="vi">@tab: </span><span class="k">if</span> <span class="nx">o</span><span class="p">.</span><span class="nx">no_wrap</span> <span class="k">then</span> <span class="s1">''</span> <span class="k">else</span> <span class="nx">TAB</span>
<span class="nv">o.scope: </span><span class="k">new</span> <span class="nx">Scope</span><span class="p">(</span><span class="kc">null</span><span class="p">,</span> <span class="k">this</span><span class="p">,</span> <span class="kc">null</span><span class="p">)</span>
<span class="nv">code: </span><span class="k">if</span> <span class="nx">o</span><span class="p">.</span><span class="nx">globals</span> <span class="k">then</span> <span class="nx">@compile_node</span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="k">else</span> <span class="nx">@compile_with_declarations</span><span class="p">(</span><span class="nx">o</span><span class="p">)</span>
<span class="nv">code: </span><span class="nx">code</span><span class="p">.</span><span class="nx">replace</span><span class="p">(</span><span class="nx">TRAILING_WHITESPACE</span><span class="p">,</span> <span class="s1">''</span><span class="p">)</span>
<span class="k">if</span> <span class="nx">o</span><span class="p">.</span><span class="nx">no_wrap</span> <span class="k">then</span> <span class="nx">code</span> <span class="k">else</span> <span class="s2">"(function(){\n$code\n})();\n"</span></pre></div> </td> </tr> <tr id="section-27"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-27">#</a> </div> <p>Compile the expressions body for the contents of a function, with
declarations of all inner variables pushed up to the top.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nv">compile_with_declarations: </span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="o">-></span>
<span class="nv">code: </span><span class="nx">@compile_node</span><span class="p">(</span><span class="nx">o</span><span class="p">)</span>
<span class="nv">code: </span><span class="s2">"${@tab}var ${o.scope.compiled_assignments()};\n$code"</span> <span class="k">if</span> <span class="nx">o</span><span class="p">.</span><span class="nx">scope</span><span class="p">.</span><span class="nx">has_assignments</span><span class="p">(</span><span class="k">this</span><span class="p">)</span>
<span class="nv">code: </span><span class="s2">"${@tab}var ${o.scope.compiled_declarations()};\n$code"</span> <span class="k">if</span> <span class="nx">o</span><span class="p">.</span><span class="nx">scope</span><span class="p">.</span><span class="nx">has_declarations</span><span class="p">(</span><span class="k">this</span><span class="p">)</span>
<span class="nx">code</span></pre></div> </td> </tr> <tr id="section-28"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-28">#</a> </div> <p>Compiles a single expression within the expressions body. If we need to
return the result, and it's an expression, simply return it. If it's a
statement, ask the statement to do so.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nv">compile_expression: </span><span class="p">(</span><span class="nx">node</span><span class="p">,</span> <span class="nx">o</span><span class="p">)</span> <span class="o">-></span>
<span class="vi">@tab: </span><span class="nx">o</span><span class="p">.</span><span class="nx">indent</span>
<span class="nv">compiled_node: </span><span class="nx">node</span><span class="p">.</span><span class="nx">compile</span> <span class="nx">merge</span> <span class="nx">o</span><span class="p">,</span> <span class="p">{</span><span class="nv">top: </span><span class="kc">true</span><span class="p">}</span>
<span class="k">if</span> <span class="nx">node</span><span class="p">.</span><span class="nx">is_statement</span><span class="p">()</span> <span class="k">then</span> <span class="nx">compiled_node</span> <span class="k">else</span> <span class="s2">"${@idt()}$compiled_node;"</span></pre></div> </td> </tr> <tr id="section-29"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-29">#</a> </div> <p>Wrap up the given nodes as an <strong>Expressions</strong>, unless it already happens
to be one.</p> </td> <td class="code"> <div class="highlight"><pre><span class="nv">Expressions.wrap: </span><span class="p">(</span><span class="nx">nodes</span><span class="p">)</span> <span class="o">-></span>
<span class="k">return</span> <span class="nx">nodes</span><span class="p">[</span><span class="mi">0</span><span class="p">]</span> <span class="k">if</span> <span class="nx">nodes</span><span class="p">.</span><span class="nx">length</span> <span class="o">is</span> <span class="mi">1</span> <span class="o">and</span> <span class="nx">nodes</span><span class="p">[</span><span class="mi">0</span><span class="p">]</span> <span class="k">instanceof</span> <span class="nx">Expressions</span>
<span class="k">new</span> <span class="nx">Expressions</span><span class="p">(</span><span class="nx">nodes</span><span class="p">)</span>
<span class="nx">children</span> <span class="nx">Expressions</span><span class="p">,</span> <span class="s1">'expressions'</span>
<span class="nx">statement</span> <span class="nx">Expressions</span></pre></div> </td> </tr> <tr id="section-30"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-30">#</a> </div> <h3>LiteralNode</h3> </td> <td class="code"> <div class="highlight"><pre></pre></div> </td> </tr> <tr id="section-31"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-31">#</a> </div> <p>Literals are static values that can be passed through directly into
JavaScript without translation, such as: strings, numbers,
<code>true</code>, <code>false</code>, <code>null</code>...</p> </td> <td class="code"> <div class="highlight"><pre><span class="nv">exports.LiteralNode: </span><span class="nx">class</span> <span class="nx">LiteralNode</span> <span class="k">extends</span> <span class="nx">BaseNode</span>
<span class="nv">constructor: </span><span class="p">(</span><span class="nx">value</span><span class="p">)</span> <span class="o">-></span>
<span class="vi">@value: </span><span class="nx">value</span></pre></div> </td> </tr> <tr id="section-32"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-32">#</a> </div> <p>Break and continue must be treated as pure statements -- they lose their
meaning when wrapped in a closure.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nv">is_statement: </span><span class="o">-></span>
<span class="nx">@value</span> <span class="o">is</span> <span class="s1">'break'</span> <span class="o">or</span> <span class="nx">@value</span> <span class="o">is</span> <span class="s1">'continue'</span>
<span class="nv">is_pure_statement: </span><span class="nx">LiteralNode</span><span class="o">::</span><span class="nx">is_statement</span>
<span class="nv">compile_node: </span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="o">-></span>
<span class="nv">idt: </span><span class="k">if</span> <span class="nx">@is_statement</span><span class="p">()</span> <span class="k">then</span> <span class="nx">@idt</span><span class="p">()</span> <span class="k">else</span> <span class="s1">''</span>
<span class="nv">end: </span><span class="k">if</span> <span class="nx">@is_statement</span><span class="p">()</span> <span class="k">then</span> <span class="s1">';'</span> <span class="k">else</span> <span class="s1">''</span>
<span class="s2">"$idt$@value$end"</span>
<span class="nv">toString: </span><span class="p">(</span><span class="nx">idt</span><span class="p">)</span> <span class="o">-></span>
<span class="s2">" \"$@value\""</span></pre></div> </td> </tr> <tr id="section-33"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-33">#</a> </div> <h3>ReturnNode</h3> </td> <td class="code"> <div class="highlight"><pre></pre></div> </td> </tr> <tr id="section-34"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-34">#</a> </div> <p>A <code>return</code> is a <em>pure_statement</em> -- wrapping it in a closure wouldn't
make sense.</p> </td> <td class="code"> <div class="highlight"><pre><span class="nv">exports.ReturnNode: </span><span class="nx">class</span> <span class="nx">ReturnNode</span> <span class="k">extends</span> <span class="nx">BaseNode</span>
<span class="nv">constructor: </span><span class="p">(</span><span class="nx">expression</span><span class="p">)</span> <span class="o">-></span>
<span class="vi">@expression: </span><span class="nx">expression</span>
<span class="nv">top_sensitive: </span><span class="o">-></span>
<span class="kc">true</span>
<span class="nv">compile_node: </span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="o">-></span>
<span class="nv">expr: </span><span class="nx">@expression</span><span class="p">.</span><span class="nx">make_return</span><span class="p">()</span>
<span class="k">return</span> <span class="nx">expr</span><span class="p">.</span><span class="nx">compile</span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="nx">unless</span> <span class="nx">expr</span> <span class="k">instanceof</span> <span class="nx">ReturnNode</span>
<span class="nx">del</span> <span class="nx">o</span><span class="p">,</span> <span class="s1">'top'</span>
<span class="nv">o.as_statement: </span><span class="kc">true</span> <span class="k">if</span> <span class="nx">@expression</span><span class="p">.</span><span class="nx">is_statement</span><span class="p">()</span>
<span class="s2">"${@tab}return ${@expression.compile(o)};"</span>
<span class="nx">statement</span> <span class="nx">ReturnNode</span><span class="p">,</span> <span class="kc">true</span>
<span class="nx">children</span> <span class="nx">ReturnNode</span><span class="p">,</span> <span class="s1">'expression'</span></pre></div> </td> </tr> <tr id="section-35"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-35">#</a> </div> <h3>ValueNode</h3> </td> <td class="code"> <div class="highlight"><pre></pre></div> </td> </tr> <tr id="section-36"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-36">#</a> </div> <p>A value, variable or literal or parenthesized, indexed or dotted into,
or vanilla.</p> </td> <td class="code"> <div class="highlight"><pre><span class="nv">exports.ValueNode: </span><span class="nx">class</span> <span class="nx">ValueNode</span> <span class="k">extends</span> <span class="nx">BaseNode</span>
<span class="nv">SOAK: </span><span class="s2">" == undefined ? undefined : "</span></pre></div> </td> </tr> <tr id="section-37"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-37">#</a> </div> <p>A <strong>ValueNode</strong> has a base and a list of property accesses.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nv">constructor: </span><span class="p">(</span><span class="nx">base</span><span class="p">,</span> <span class="nx">properties</span><span class="p">)</span> <span class="o">-></span>
<span class="vi">@base: </span><span class="nx">base</span>
<span class="vi">@properties: </span><span class="p">(</span><span class="nx">properties</span> <span class="o">or</span> <span class="p">[])</span></pre></div> </td> </tr> <tr id="section-38"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-38">#</a> </div> <p>Add a property access to the list.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nv">push: </span><span class="p">(</span><span class="nx">prop</span><span class="p">)</span> <span class="o">-></span>
<span class="nx">@properties</span><span class="p">.</span><span class="nx">push</span><span class="p">(</span><span class="nx">prop</span><span class="p">)</span>
<span class="k">this</span>
<span class="nv">has_properties: </span><span class="o">-></span>
<span class="o">!!</span><span class="nx">@properties</span><span class="p">.</span><span class="nx">length</span></pre></div> </td> </tr> <tr id="section-39"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-39">#</a> </div> <p>Some boolean checks for the benefit of other nodes.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nv">is_array: </span><span class="o">-></span>
<span class="nx">@base</span> <span class="k">instanceof</span> <span class="nx">ArrayNode</span> <span class="o">and</span> <span class="o">not</span> <span class="nx">@has_properties</span><span class="p">()</span>
<span class="nv">is_object: </span><span class="o">-></span>
<span class="nx">@base</span> <span class="k">instanceof</span> <span class="nx">ObjectNode</span> <span class="o">and</span> <span class="o">not</span> <span class="nx">@has_properties</span><span class="p">()</span>
<span class="nv">is_splice: </span><span class="o">-></span>
<span class="nx">@has_properties</span><span class="p">()</span> <span class="o">and</span> <span class="nx">@properties</span><span class="p">[</span><span class="nx">@properties</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="k">instanceof</span> <span class="nx">SliceNode</span>
<span class="nv">make_return: </span><span class="o">-></span>
<span class="k">if</span> <span class="nx">@has_properties</span><span class="p">()</span> <span class="k">then</span> <span class="k">super</span><span class="p">()</span> <span class="k">else</span> <span class="nx">@base</span><span class="p">.</span><span class="nx">make_return</span><span class="p">()</span></pre></div> </td> </tr> <tr id="section-40"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-40">#</a> </div> <p>The value can be unwrapped as its inner node, if there are no attached
properties.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nv">unwrap: </span><span class="o">-></span>
<span class="k">if</span> <span class="nx">@properties</span><span class="p">.</span><span class="nx">length</span> <span class="k">then</span> <span class="k">this</span> <span class="k">else</span> <span class="nx">@base</span></pre></div> </td> </tr> <tr id="section-41"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-41">#</a> </div> <p>Values are considered to be statements if their base is a statement.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nv">is_statement: </span><span class="o">-></span>
<span class="nx">@base</span><span class="p">.</span><span class="nx">is_statement</span> <span class="o">and</span> <span class="nx">@base</span><span class="p">.</span><span class="nx">is_statement</span><span class="p">()</span> <span class="o">and</span> <span class="o">not</span> <span class="nx">@has_properties</span><span class="p">()</span></pre></div> </td> </tr> <tr id="section-42"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-42">#</a> </div> <p>Works out if the value is the start of a chain.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nv">is_start: </span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="o">-></span>
<span class="k">return</span> <span class="kc">true</span> <span class="k">if</span> <span class="k">this</span> <span class="o">is</span> <span class="nx">o</span><span class="p">.</span><span class="nx">chain_root</span> <span class="o">and</span> <span class="nx">@properties</span><span class="p">[</span><span class="mi">0</span><span class="p">]</span> <span class="k">instanceof</span> <span class="nx">AccessorNode</span>
<span class="nv">node: </span><span class="nx">o</span><span class="p">.</span><span class="nx">chain_root</span><span class="p">.</span><span class="nx">base</span> <span class="o">or</span> <span class="nx">o</span><span class="p">.</span><span class="nx">chain_root</span><span class="p">.</span><span class="nx">variable</span>
<span class="k">while</span> <span class="nx">node</span> <span class="k">instanceof</span> <span class="nx">CallNode</span> <span class="k">then</span> <span class="nv">node: </span><span class="nx">node</span><span class="p">.</span><span class="nx">variable</span>
<span class="nx">node</span> <span class="o">is</span> <span class="k">this</span></pre></div> </td> </tr> <tr id="section-43"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-43">#</a> </div> <p>We compile a value to JavaScript by compiling and joining each property.
Things get much more insteresting if the chain of properties has <em>soak</em>
operators <code>?.</code> interspersed. Then we have to take care not to accidentally
evaluate a anything twice when building the soak chain.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nv">compile_node: </span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="o">-></span>
<span class="nv">only: </span> <span class="nx">del</span><span class="p">(</span><span class="nx">o</span><span class="p">,</span> <span class="s1">'only_first'</span><span class="p">)</span>
<span class="nv">op: </span> <span class="nx">del</span><span class="p">(</span><span class="nx">o</span><span class="p">,</span> <span class="s1">'operation'</span><span class="p">)</span>
<span class="nv">props: </span> <span class="k">if</span> <span class="nx">only</span> <span class="k">then</span> <span class="nx">@properties</span><span class="p">[</span><span class="mi">0</span><span class="p">...</span><span class="nx">@properties</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="k">else</span> <span class="nx">@properties</span>
<span class="nv">o.chain_root: </span><span class="o">or</span> <span class="k">this</span>
<span class="nv">baseline: </span> <span class="nx">@base</span><span class="p">.</span><span class="nx">compile</span> <span class="nx">o</span>
<span class="nv">baseline: </span> <span class="s2">"($baseline)"</span> <span class="k">if</span> <span class="nx">@base</span> <span class="k">instanceof</span> <span class="nx">ObjectNode</span> <span class="o">and</span> <span class="nx">@has_properties</span><span class="p">()</span>
<span class="nv">complete: </span> <span class="vi">@last: </span><span class="nx">baseline</span>
<span class="k">for</span> <span class="nx">prop</span><span class="p">,</span> <span class="nx">i</span> <span class="k">in</span> <span class="nx">props</span>
<span class="vi">@source: </span><span class="nx">baseline</span>
<span class="k">if</span> <span class="nx">prop</span><span class="p">.</span><span class="nx">soak_node</span>
<span class="k">if</span> <span class="nx">@base</span> <span class="k">instanceof</span> <span class="nx">CallNode</span> <span class="o">and</span> <span class="nx">i</span> <span class="o">is</span> <span class="mi">0</span>
<span class="nv">temp: </span><span class="nx">o</span><span class="p">.</span><span class="nx">scope</span><span class="p">.</span><span class="nx">free_variable</span><span class="p">()</span>
<span class="nv">complete: </span><span class="s2">"(${ baseline: temp } = ($complete))"</span>
<span class="nv">complete: </span><span class="s2">"typeof $complete === \"undefined\" || $baseline"</span> <span class="k">if</span> <span class="nx">i</span> <span class="o">is</span> <span class="mi">0</span> <span class="o">and</span> <span class="nx">@is_start</span><span class="p">(</span><span class="nx">o</span><span class="p">)</span>
<span class="nv">complete: </span><span class="o">+</span> <span class="nx">@SOAK</span> <span class="o">+</span> <span class="p">(</span><span class="nv">baseline: </span><span class="o">+</span> <span class="nx">prop</span><span class="p">.</span><span class="nx">compile</span><span class="p">(</span><span class="nx">o</span><span class="p">))</span>
<span class="k">else</span>
<span class="nv">part: </span><span class="nx">prop</span><span class="p">.</span><span class="nx">compile</span><span class="p">(</span><span class="nx">o</span><span class="p">)</span>
<span class="nv">baseline: </span><span class="o">+</span> <span class="nx">part</span>
<span class="nv">complete: </span><span class="o">+</span> <span class="nx">part</span>
<span class="vi">@last: </span><span class="nx">part</span>
<span class="k">if</span> <span class="nx">op</span> <span class="o">and</span> <span class="nx">@wrapped</span> <span class="k">then</span> <span class="s2">"($complete)"</span> <span class="k">else</span> <span class="nx">complete</span>
<span class="nx">children</span> <span class="nx">ValueNode</span><span class="p">,</span> <span class="s1">'base'</span><span class="p">,</span> <span class="s1">'properties'</span></pre></div> </td> </tr> <tr id="section-44"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-44">#</a> </div> <h3>CommentNode</h3> </td> <td class="code"> <div class="highlight"><pre></pre></div> </td> </tr> <tr id="section-45"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-45">#</a> </div> <p>CoffeeScript passes through comments as JavaScript comments at the
same position.</p> </td> <td class="code"> <div class="highlight"><pre><span class="nv">exports.CommentNode: </span><span class="nx">class</span> <span class="nx">CommentNode</span> <span class="k">extends</span> <span class="nx">BaseNode</span>
<span class="nv">constructor: </span><span class="p">(</span><span class="nx">lines</span><span class="p">,</span> <span class="nx">type</span><span class="p">)</span> <span class="o">-></span>
<span class="vi">@lines: </span><span class="nx">lines</span>
<span class="vi">@type: </span><span class="nx">type</span>
<span class="k">this</span>
<span class="nv">make_return: </span><span class="o">-></span>
<span class="k">this</span>
<span class="nv">compile_node: </span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="o">-></span>
<span class="k">if</span> <span class="nx">@type</span> <span class="o">is</span> <span class="s1">'herecomment'</span>
<span class="nv">sep: </span><span class="s1">'\n'</span> <span class="o">+</span> <span class="nx">@tab</span>
<span class="s2">"$@tab/*$sep${ @lines.join(sep) }\n$@tab*/"</span>
<span class="k">else</span>
<span class="s2">"$@tab//"</span> <span class="o">+</span> <span class="nx">@lines</span><span class="p">.</span><span class="nx">join</span><span class="p">(</span><span class="s2">"\n$@tab//"</span><span class="p">)</span>
<span class="nx">statement</span> <span class="nx">CommentNode</span></pre></div> </td> </tr> <tr id="section-46"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-46">#</a> </div> <h3>CallNode</h3> </td> <td class="code"> <div class="highlight"><pre></pre></div> </td> </tr> <tr id="section-47"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-47">#</a> </div> <p>Node for a function invocation. Takes care of converting <code>super()</code> calls into
calls against the prototype's function of the same name.</p> </td> <td class="code"> <div class="highlight"><pre><span class="nv">exports.CallNode: </span><span class="nx">class</span> <span class="nx">CallNode</span> <span class="k">extends</span> <span class="nx">BaseNode</span>
<span class="nv">constructor: </span><span class="p">(</span><span class="nx">variable</span><span class="p">,</span> <span class="nx">args</span><span class="p">)</span> <span class="o">-></span>
<span class="vi">@is_new: </span> <span class="kc">false</span>
<span class="vi">@is_super: </span><span class="nx">variable</span> <span class="o">is</span> <span class="s1">'super'</span>
<span class="vi">@variable: </span><span class="k">if</span> <span class="nx">@is_super</span> <span class="k">then</span> <span class="kc">null</span> <span class="k">else</span> <span class="nx">variable</span>
<span class="vi">@args: </span><span class="p">(</span><span class="nx">args</span> <span class="o">or</span> <span class="p">[])</span>
<span class="vi">@compile_splat_arguments: </span><span class="nx">SplatNode</span><span class="p">.</span><span class="nx">compile_mixed_array</span> <span class="o"><-</span> <span class="err">@</span><span class="p">,</span> <span class="nx">@args</span></pre></div> </td> </tr> <tr id="section-48"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-48">#</a> </div> <p>Tag this invocation as creating a new instance.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nv">new_instance: </span><span class="o">-></span>
<span class="vi">@is_new: </span><span class="kc">true</span>
<span class="k">this</span>
<span class="nv">prefix: </span><span class="o">-></span>
<span class="k">if</span> <span class="nx">@is_new</span> <span class="k">then</span> <span class="s1">'new '</span> <span class="k">else</span> <span class="s1">''</span></pre></div> </td> </tr> <tr id="section-49"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-49">#</a> </div> <p>Grab the reference to the superclass' implementation of the current method.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nv">super_reference: </span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="o">-></span>
<span class="nv">methname: </span><span class="nx">o</span><span class="p">.</span><span class="nx">scope</span><span class="p">.</span><span class="nx">method</span><span class="p">.</span><span class="nx">name</span>
<span class="nv">meth: </span><span class="k">if</span> <span class="nx">o</span><span class="p">.</span><span class="nx">scope</span><span class="p">.</span><span class="nx">method</span><span class="p">.</span><span class="nx">proto</span>
<span class="s2">"${o.scope.method.proto}.__superClass__.$methname"</span>
<span class="k">else</span> <span class="k">if</span> <span class="nx">methname</span>
<span class="s2">"${methname}.__superClass__.constructor"</span>
<span class="k">else</span> <span class="k">throw</span> <span class="k">new</span> <span class="nb">Error</span> <span class="s2">"cannot call super on an anonymous function."</span></pre></div> </td> </tr> <tr id="section-50"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-50">#</a> </div> <p>Compile a vanilla function call.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nv">compile_node: </span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="o">-></span>
<span class="nv">o.chain_root: </span><span class="k">this</span> <span class="nx">unless</span> <span class="nx">o</span><span class="p">.</span><span class="nx">chain_root</span>
<span class="k">for</span> <span class="nx">arg</span> <span class="k">in</span> <span class="nx">@args</span> <span class="k">when</span> <span class="nx">arg</span> <span class="k">instanceof</span> <span class="nx">SplatNode</span>
<span class="nv">compilation: </span><span class="nx">@compile_splat</span><span class="p">(</span><span class="nx">o</span><span class="p">)</span>
<span class="nx">unless</span> <span class="nx">compilation</span>
<span class="nv">args: </span><span class="p">(</span><span class="nx">arg</span><span class="p">.</span><span class="nx">compile</span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="k">for</span> <span class="nx">arg</span> <span class="k">in</span> <span class="nx">@args</span><span class="p">).</span><span class="nx">join</span><span class="p">(</span><span class="s1">', '</span><span class="p">)</span>
<span class="nv">compilation: </span><span class="k">if</span> <span class="nx">@is_super</span> <span class="k">then</span> <span class="nx">@compile_super</span><span class="p">(</span><span class="nx">args</span><span class="p">,</span> <span class="nx">o</span><span class="p">)</span>
<span class="k">else</span> <span class="s2">"${@prefix()}${@variable.compile(o)}($args)"</span>
<span class="k">if</span> <span class="nx">o</span><span class="p">.</span><span class="nx">operation</span> <span class="o">and</span> <span class="nx">@wrapped</span> <span class="k">then</span> <span class="s2">"($compilation)"</span> <span class="k">else</span> <span class="nx">compilation</span></pre></div> </td> </tr> <tr id="section-51"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-51">#</a> </div> <p><code>super()</code> is converted into a call against the superclass's implementation
of the current function.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nv">compile_super: </span><span class="p">(</span><span class="nx">args</span><span class="p">,</span> <span class="nx">o</span><span class="p">)</span> <span class="o">-></span>
<span class="s2">"${@super_reference(o)}.call(this${ if args.length then ', ' else '' }$args)"</span></pre></div> </td> </tr> <tr id="section-52"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-52">#</a> </div> <p>If you call a function with a splat, it's converted into a JavaScript
<code>.apply()</code> call to allow an array of arguments to be passed.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nv">compile_splat: </span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="o">-></span>
<span class="nv">meth: </span><span class="k">if</span> <span class="nx">@variable</span> <span class="k">then</span> <span class="nx">@variable</span><span class="p">.</span><span class="nx">compile</span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="k">else</span> <span class="nx">@super_reference</span><span class="p">(</span><span class="nx">o</span><span class="p">)</span>
<span class="nv">obj: </span> <span class="nx">@variable</span> <span class="o">and</span> <span class="nx">@variable</span><span class="p">.</span><span class="nx">source</span> <span class="o">or</span> <span class="s1">'this'</span>
<span class="k">if</span> <span class="nx">obj</span><span class="p">.</span><span class="nx">match</span><span class="p">(</span><span class="sr">/\(/</span><span class="p">)</span>
<span class="nv">temp: </span><span class="nx">o</span><span class="p">.</span><span class="nx">scope</span><span class="p">.</span><span class="nx">free_variable</span><span class="p">()</span>
<span class="nv">obj: </span> <span class="nx">temp</span>
<span class="nv">meth: </span><span class="s2">"($temp = ${ @variable.source })${ @variable.last }"</span>
<span class="s2">"${@prefix()}${meth}.apply($obj, ${ @compile_splat_arguments(o) })"</span>
<span class="nx">children</span> <span class="nx">CallNode</span><span class="p">,</span> <span class="s1">'variable'</span><span class="p">,</span> <span class="s1">'args'</span></pre></div> </td> </tr> <tr id="section-53"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-53">#</a> </div> <h3>CurryNode</h3> </td> <td class="code"> <div class="highlight"><pre></pre></div> </td> </tr> <tr id="section-54"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-54">#</a> </div> <p>Binds a context object and a list of arguments to a function,
returning the bound function. After ECMAScript 5, Prototype.js, and
Underscore's <code>bind</code> functions.</p> </td> <td class="code"> <div class="highlight"><pre><span class="nv">exports.CurryNode: </span><span class="nx">class</span> <span class="nx">CurryNode</span> <span class="k">extends</span> <span class="nx">CallNode</span>
<span class="nv">constructor: </span><span class="p">(</span><span class="nx">meth</span><span class="p">,</span> <span class="nx">args</span><span class="p">)</span> <span class="o">-></span>
<span class="vi">@meth: </span><span class="nx">meth</span>
<span class="vi">@context: </span><span class="nx">args</span><span class="p">[</span><span class="mi">0</span><span class="p">]</span>
<span class="vi">@args: </span><span class="p">(</span><span class="nx">args</span><span class="p">.</span><span class="nx">slice</span><span class="p">(</span><span class="mi">1</span><span class="p">)</span> <span class="o">or</span> <span class="p">[])</span>
<span class="vi">@compile_splat_arguments: </span><span class="nx">SplatNode</span><span class="p">.</span><span class="nx">compile_mixed_array</span> <span class="o"><-</span> <span class="err">@</span><span class="p">,</span> <span class="nx">@args</span>
<span class="nv">arguments: </span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="o">-></span>
<span class="k">for</span> <span class="nx">arg</span> <span class="k">in</span> <span class="nx">@args</span>
<span class="k">return</span> <span class="nx">@compile_splat_arguments</span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="k">if</span> <span class="nx">arg</span> <span class="k">instanceof</span> <span class="nx">SplatNode</span>
<span class="p">(</span><span class="k">new</span> <span class="nx">ArrayNode</span><span class="p">(</span><span class="nx">@args</span><span class="p">)).</span><span class="nx">compile</span> <span class="nx">o</span>
<span class="nv">compile_node: </span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="o">-></span>
<span class="nx">utility</span> <span class="s1">'slice'</span>
<span class="nv">ref: </span><span class="k">new</span> <span class="nx">ValueNode</span> <span class="nx">literal</span> <span class="nx">utility</span> <span class="s1">'bind'</span>
<span class="p">(</span><span class="k">new</span> <span class="nx">CallNode</span><span class="p">(</span><span class="nx">ref</span><span class="p">,</span> <span class="p">[</span><span class="nx">@meth</span><span class="p">,</span> <span class="nx">@context</span><span class="p">,</span> <span class="nx">literal</span><span class="p">(</span><span class="nx">@arguments</span><span class="p">(</span><span class="nx">o</span><span class="p">))])).</span><span class="nx">compile</span> <span class="nx">o</span>
<span class="nx">children</span> <span class="nx">CurryNode</span><span class="p">,</span> <span class="s1">'meth'</span><span class="p">,</span> <span class="s1">'context'</span><span class="p">,</span> <span class="s1">'args'</span></pre></div> </td> </tr> <tr id="section-55"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-55">#</a> </div> <h3>ExtendsNode</h3> </td> <td class="code"> <div class="highlight"><pre></pre></div> </td> </tr> <tr id="section-56"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-56">#</a> </div> <p>Node to extend an object's prototype with an ancestor object.
After <code>goog.inherits</code> from the
<a href="http://closure-library.googlecode.com/svn/docs/closure_goog_base.js.html">Closure Library</a>.</p> </td> <td class="code"> <div class="highlight"><pre><span class="nv">exports.ExtendsNode: </span><span class="nx">class</span> <span class="nx">ExtendsNode</span> <span class="k">extends</span> <span class="nx">BaseNode</span>
<span class="nv">constructor: </span><span class="p">(</span><span class="nx">child</span><span class="p">,</span> <span class="nx">parent</span><span class="p">)</span> <span class="o">-></span>
<span class="vi">@child: </span><span class="nx">child</span>
<span class="vi">@parent: </span><span class="nx">parent</span></pre></div> </td> </tr> <tr id="section-57"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-57">#</a> </div> <p>Hooks one constructor into another's prototype chain.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nv">compile_node: </span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="o">-></span>
<span class="nv">ref: </span> <span class="k">new</span> <span class="nx">ValueNode</span> <span class="nx">literal</span> <span class="nx">utility</span> <span class="s1">'extends'</span>
<span class="p">(</span><span class="k">new</span> <span class="nx">CallNode</span> <span class="nx">ref</span><span class="p">,</span> <span class="p">[</span><span class="nx">@child</span><span class="p">,</span> <span class="nx">@parent</span><span class="p">]).</span><span class="nx">compile</span> <span class="nx">o</span>
<span class="nx">children</span> <span class="nx">ExtendsNode</span><span class="p">,</span> <span class="s1">'child'</span><span class="p">,</span> <span class="s1">'parent'</span></pre></div> </td> </tr> <tr id="section-58"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-58">#</a> </div> <h3>AccessorNode</h3> </td> <td class="code"> <div class="highlight"><pre></pre></div> </td> </tr> <tr id="section-59"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-59">#</a> </div> <p>A <code>.</code> accessor into a property of a value, or the <code>::</code> shorthand for
an accessor into the object's prototype.</p> </td> <td class="code"> <div class="highlight"><pre><span class="nv">exports.AccessorNode: </span><span class="nx">class</span> <span class="nx">AccessorNode</span> <span class="k">extends</span> <span class="nx">BaseNode</span>
<span class="nv">constructor: </span><span class="p">(</span><span class="nx">name</span><span class="p">,</span> <span class="nx">tag</span><span class="p">)</span> <span class="o">-></span>
<span class="vi">@name: </span><span class="nx">name</span>
<span class="vi">@prototype: </span><span class="nx">tag</span> <span class="o">is</span> <span class="s1">'prototype'</span>
<span class="vi">@soak_node: </span><span class="nx">tag</span> <span class="o">is</span> <span class="s1">'soak'</span>
<span class="k">this</span>
<span class="nv">compile_node: </span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="o">-></span>
<span class="nv">o.chain_root.wrapped: </span><span class="o">or</span> <span class="nx">@soak_node</span>
<span class="nv">proto_part: </span><span class="k">if</span> <span class="nx">@prototype</span> <span class="k">then</span> <span class="s1">'prototype.'</span> <span class="k">else</span> <span class="s1">''</span>
<span class="s2">".$proto_part${@name.compile(o)}"</span>
<span class="nx">children</span> <span class="nx">AccessorNode</span><span class="p">,</span> <span class="s1">'name'</span></pre></div> </td> </tr> <tr id="section-60"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-60">#</a> </div> <h3>IndexNode</h3> </td> <td class="code"> <div class="highlight"><pre></pre></div> </td> </tr> <tr id="section-61"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-61">#</a> </div> <p>A <code>[ ... ]</code> indexed accessor into an array or object.</p> </td> <td class="code"> <div class="highlight"><pre><span class="nv">exports.IndexNode: </span><span class="nx">class</span> <span class="nx">IndexNode</span> <span class="k">extends</span> <span class="nx">BaseNode</span>
<span class="nv">constructor: </span><span class="p">(</span><span class="nx">index</span><span class="p">,</span> <span class="nx">tag</span><span class="p">)</span> <span class="o">-></span>
<span class="vi">@index: </span><span class="nx">index</span>
<span class="vi">@soak_node: </span><span class="nx">tag</span> <span class="o">is</span> <span class="s1">'soak'</span>
<span class="nv">compile_node: </span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="o">-></span>
<span class="nv">o.chain_root.wrapped: </span><span class="o">or</span> <span class="nx">@soak_node</span>
<span class="nv">idx: </span><span class="nx">@index</span><span class="p">.</span><span class="nx">compile</span> <span class="nx">o</span>
<span class="s2">"[$idx]"</span>
<span class="nx">children</span> <span class="nx">IndexNode</span><span class="p">,</span> <span class="s1">'index'</span></pre></div> </td> </tr> <tr id="section-62"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-62">#</a> </div> <h3>RangeNode</h3> </td> <td class="code"> <div class="highlight"><pre></pre></div> </td> </tr> <tr id="section-63"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-63">#</a> </div> <p>A range literal. Ranges can be used to extract portions (slices) of arrays,
to specify a range for comprehensions, or as a value, to be expanded into the
corresponding array of integers at runtime.</p> </td> <td class="code"> <div class="highlight"><pre><span class="nv">exports.RangeNode: </span><span class="nx">class</span> <span class="nx">RangeNode</span> <span class="k">extends</span> <span class="nx">BaseNode</span>
<span class="nv">constructor: </span><span class="p">(</span><span class="nx">from</span><span class="p">,</span> <span class="nx">to</span><span class="p">,</span> <span class="nx">exclusive</span><span class="p">)</span> <span class="o">-></span>
<span class="vi">@from: </span><span class="nx">from</span>
<span class="vi">@to: </span><span class="nx">to</span>
<span class="vi">@exclusive: </span><span class="o">!!</span><span class="nx">exclusive</span></pre></div> </td> </tr> <tr id="section-64"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-64">#</a> </div> <p>Compiles the range's source variables -- where it starts and where it ends.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nv">compile_variables: </span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="o">-></span>
<span class="vi">@tab: </span><span class="nx">o</span><span class="p">.</span><span class="nx">indent</span>
<span class="p">[</span><span class="nx">@from_var</span><span class="p">,</span> <span class="nx">@to_var</span><span class="p">]</span><span class="o">:</span> <span class="p">[</span><span class="nx">o</span><span class="p">.</span><span class="nx">scope</span><span class="p">.</span><span class="nx">free_variable</span><span class="p">(),</span> <span class="nx">o</span><span class="p">.</span><span class="nx">scope</span><span class="p">.</span><span class="nx">free_variable</span><span class="p">()]</span>
<span class="p">[</span><span class="nx">from</span><span class="p">,</span> <span class="nx">to</span><span class="p">]</span><span class="o">:</span> <span class="p">[</span><span class="nx">@from</span><span class="p">.</span><span class="nx">compile</span><span class="p">(</span><span class="nx">o</span><span class="p">),</span> <span class="nx">@to</span><span class="p">.</span><span class="nx">compile</span><span class="p">(</span><span class="nx">o</span><span class="p">)]</span>
<span class="s2">"$@from_var = $from; $@to_var = $to;\n$@tab"</span></pre></div> </td> </tr> <tr id="section-65"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-65">#</a> </div> <p>When compiled normally, the range returns the contents of the <em>for loop</em>
needed to iterate over the values in the range. Used by comprehensions.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nv">compile_node: </span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="o">-></span>
<span class="k">return</span> <span class="nx">@compile_array</span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="nx">unless</span> <span class="nx">o</span><span class="p">.</span><span class="nx">index</span>
<span class="nv">idx: </span> <span class="nx">del</span> <span class="nx">o</span><span class="p">,</span> <span class="s1">'index'</span>
<span class="nv">step: </span> <span class="nx">del</span> <span class="nx">o</span><span class="p">,</span> <span class="s1">'step'</span>
<span class="nv">vars: </span> <span class="s2">"$idx = $@from_var"</span>
<span class="nv">step: </span> <span class="k">if</span> <span class="nx">step</span> <span class="k">then</span> <span class="nx">step</span><span class="p">.</span><span class="nx">compile</span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="k">else</span> <span class="s1">'1'</span>
<span class="nv">equals: </span> <span class="k">if</span> <span class="nx">@exclusive</span> <span class="k">then</span> <span class="s1">''</span> <span class="k">else</span> <span class="s1">'='</span>
<span class="nv">intro: </span> <span class="s2">"($@from_var <= $@to_var ? $idx"</span>
<span class="nv">compare: </span> <span class="s2">"$intro <$equals $@to_var : $idx >$equals $@to_var)"</span>
<span class="nv">incr: </span> <span class="s2">"$intro += $step : $idx -= $step)"</span>
<span class="s2">"$vars; $compare; $incr"</span></pre></div> </td> </tr> <tr id="section-66"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-66">#</a> </div> <p>When used as a value, expand the range into the equivalent array. In the
future, the code this generates should probably be cleaned up by handwriting
it instead of wrapping nodes.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nv">compile_array: </span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="o">-></span>
<span class="nv">name: </span><span class="nx">o</span><span class="p">.</span><span class="nx">scope</span><span class="p">.</span><span class="nx">free_variable</span><span class="p">()</span>
<span class="nv">body: </span><span class="nx">Expressions</span><span class="p">.</span><span class="nx">wrap</span><span class="p">([</span><span class="nx">literal</span><span class="p">(</span><span class="nx">name</span><span class="p">)])</span>
<span class="nv">arr: </span> <span class="nx">Expressions</span><span class="p">.</span><span class="nx">wrap</span><span class="p">([</span><span class="k">new</span> <span class="nx">ForNode</span><span class="p">(</span><span class="nx">body</span><span class="p">,</span> <span class="p">{</span><span class="nv">source: </span><span class="p">(</span><span class="k">new</span> <span class="nx">ValueNode</span><span class="p">(</span><span class="k">this</span><span class="p">))},</span> <span class="nx">literal</span><span class="p">(</span><span class="nx">name</span><span class="p">))])</span>
<span class="p">(</span><span class="k">new</span> <span class="nx">ParentheticalNode</span><span class="p">(</span><span class="k">new</span> <span class="nx">CallNode</span><span class="p">(</span><span class="k">new</span> <span class="nx">CodeNode</span><span class="p">([],</span> <span class="nx">arr</span><span class="p">.</span><span class="nx">make_return</span><span class="p">())))).</span><span class="nx">compile</span><span class="p">(</span><span class="nx">o</span><span class="p">)</span>
<span class="nx">children</span> <span class="nx">RangeNode</span><span class="p">,</span> <span class="s1">'from'</span><span class="p">,</span> <span class="s1">'to'</span></pre></div> </td> </tr> <tr id="section-67"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-67">#</a> </div> <h3>SliceNode</h3> </td> <td class="code"> <div class="highlight"><pre></pre></div> </td> </tr> <tr id="section-68"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-68">#</a> </div> <p>An array slice literal. Unlike JavaScript's <code>Array#slice</code>, the second parameter
specifies the index of the end of the slice, just as the first parameter
is the index of the beginning.</p> </td> <td class="code"> <div class="highlight"><pre><span class="nv">exports.SliceNode: </span><span class="nx">class</span> <span class="nx">SliceNode</span> <span class="k">extends</span> <span class="nx">BaseNode</span>
<span class="nv">constructor: </span><span class="p">(</span><span class="nx">range</span><span class="p">)</span> <span class="o">-></span>
<span class="vi">@range: </span><span class="nx">range</span>
<span class="k">this</span>
<span class="nv">compile_node: </span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="o">-></span>
<span class="nv">from: </span> <span class="nx">@range</span><span class="p">.</span><span class="nx">from</span><span class="p">.</span><span class="nx">compile</span><span class="p">(</span><span class="nx">o</span><span class="p">)</span>
<span class="nv">to: </span> <span class="nx">@range</span><span class="p">.</span><span class="nx">to</span><span class="p">.</span><span class="nx">compile</span><span class="p">(</span><span class="nx">o</span><span class="p">)</span>
<span class="nv">plus_part: </span> <span class="k">if</span> <span class="nx">@range</span><span class="p">.</span><span class="nx">exclusive</span> <span class="k">then</span> <span class="s1">''</span> <span class="k">else</span> <span class="s1">' + 1'</span>
<span class="s2">".slice($from, $to$plus_part)"</span>
<span class="nx">children</span> <span class="nx">SliceNode</span><span class="p">,</span> <span class="s1">'range'</span></pre></div> </td> </tr> <tr id="section-69"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-69">#</a> </div> <h3>ObjectNode</h3> </td> <td class="code"> <div class="highlight"><pre></pre></div> </td> </tr> <tr id="section-70"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-70">#</a> </div> <p>An object literal, nothing fancy.</p> </td> <td class="code"> <div class="highlight"><pre><span class="nv">exports.ObjectNode: </span><span class="nx">class</span> <span class="nx">ObjectNode</span> <span class="k">extends</span> <span class="nx">BaseNode</span>
<span class="nv">constructor: </span><span class="p">(</span><span class="nx">props</span><span class="p">)</span> <span class="o">-></span>
<span class="vi">@objects: @properties: </span><span class="nx">props</span> <span class="o">or</span> <span class="p">[]</span></pre></div> </td> </tr> <tr id="section-71"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-71">#</a> </div> <p>All the mucking about with commas is to make sure that CommentNodes and
AssignNodes get interleaved correctly, with no trailing commas or
commas affixed to comments.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nv">compile_node: </span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="o">-></span>
<span class="nv">o.indent: </span><span class="nx">@idt</span> <span class="mi">1</span>
<span class="nv">non_comments: </span><span class="nx">prop</span> <span class="k">for</span> <span class="nx">prop</span> <span class="k">in</span> <span class="nx">@properties</span> <span class="k">when</span> <span class="o">not</span> <span class="p">(</span><span class="nx">prop</span> <span class="k">instanceof</span> <span class="nx">CommentNode</span><span class="p">)</span>
<span class="nv">last_noncom: </span> <span class="nx">non_comments</span><span class="p">[</span><span class="nx">non_comments</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="nv">props: </span><span class="k">for</span> <span class="nx">prop</span><span class="p">,</span> <span class="nx">i</span> <span class="k">in</span> <span class="nx">@properties</span>
<span class="nv">join: </span> <span class="s2">",\n"</span>
<span class="nv">join: </span> <span class="s2">"\n"</span> <span class="k">if</span> <span class="p">(</span><span class="nx">prop</span> <span class="o">is</span> <span class="nx">last_noncom</span><span class="p">)</span> <span class="o">or</span> <span class="p">(</span><span class="nx">prop</span> <span class="k">instanceof</span> <span class="nx">CommentNode</span><span class="p">)</span>
<span class="nv">join: </span> <span class="s1">''</span> <span class="k">if</span> <span class="nx">i</span> <span class="o">is</span> <span class="nx">@properties</span><span class="p">.</span><span class="nx">length</span> <span class="o">-</span> <span class="mi">1</span>
<span class="nv">indent: </span><span class="k">if</span> <span class="nx">prop</span> <span class="k">instanceof</span> <span class="nx">CommentNode</span> <span class="k">then</span> <span class="s1">''</span> <span class="k">else</span> <span class="nx">@idt</span> <span class="mi">1</span>
<span class="nv">prop: </span> <span class="k">new</span> <span class="nx">AssignNode</span> <span class="nx">prop</span><span class="p">,</span> <span class="nx">prop</span><span class="p">,</span> <span class="s1">'object'</span> <span class="nx">unless</span> <span class="nx">prop</span> <span class="k">instanceof</span> <span class="nx">AssignNode</span> <span class="o">or</span> <span class="nx">prop</span> <span class="k">instanceof</span> <span class="nx">CommentNode</span>
<span class="nx">indent</span> <span class="o">+</span> <span class="nx">prop</span><span class="p">.</span><span class="nx">compile</span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="o">+</span> <span class="nx">join</span>
<span class="nv">props: </span><span class="nx">props</span><span class="p">.</span><span class="nx">join</span><span class="p">(</span><span class="s1">''</span><span class="p">)</span>
<span class="nv">inner: </span><span class="k">if</span> <span class="nx">props</span> <span class="k">then</span> <span class="s1">'\n'</span> <span class="o">+</span> <span class="nx">props</span> <span class="o">+</span> <span class="s1">'\n'</span> <span class="o">+</span> <span class="nx">@idt</span><span class="p">()</span> <span class="k">else</span> <span class="s1">''</span>
<span class="s2">"{$inner}"</span>
<span class="nx">children</span> <span class="nx">ObjectNode</span><span class="p">,</span> <span class="s1">'properties'</span></pre></div> </td> </tr> <tr id="section-72"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-72">#</a> </div> <h3>ArrayNode</h3> </td> <td class="code"> <div class="highlight"><pre></pre></div> </td> </tr> <tr id="section-73"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-73">#</a> </div> <p>An array literal.</p> </td> <td class="code"> <div class="highlight"><pre><span class="nv">exports.ArrayNode: </span><span class="nx">class</span> <span class="nx">ArrayNode</span> <span class="k">extends</span> <span class="nx">BaseNode</span>
<span class="nv">constructor: </span><span class="p">(</span><span class="nx">objects</span><span class="p">)</span> <span class="o">-></span>
<span class="vi">@objects: </span><span class="nx">objects</span> <span class="o">or</span> <span class="p">[]</span>
<span class="vi">@compile_splat_literal: </span><span class="nx">SplatNode</span><span class="p">.</span><span class="nx">compile_mixed_array</span> <span class="o"><-</span> <span class="err">@</span><span class="p">,</span> <span class="nx">@objects</span>
<span class="nv">compile_node: </span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="o">-></span>
<span class="nv">o.indent: </span><span class="nx">@idt</span> <span class="mi">1</span>
<span class="nv">objects: </span><span class="p">[]</span>
<span class="k">for</span> <span class="nx">obj</span><span class="p">,</span> <span class="nx">i</span> <span class="k">in</span> <span class="nx">@objects</span>
<span class="nv">code: </span><span class="nx">obj</span><span class="p">.</span><span class="nx">compile</span><span class="p">(</span><span class="nx">o</span><span class="p">)</span>
<span class="k">if</span> <span class="nx">obj</span> <span class="k">instanceof</span> <span class="nx">SplatNode</span>
<span class="k">return</span> <span class="nx">@compile_splat_literal</span> <span class="nx">@objects</span><span class="p">,</span> <span class="nx">o</span>
<span class="k">else</span> <span class="k">if</span> <span class="nx">obj</span> <span class="k">instanceof</span> <span class="nx">CommentNode</span>
<span class="nx">objects</span><span class="p">.</span><span class="nx">push</span> <span class="s2">"\n$code\n$o.indent"</span>
<span class="k">else</span> <span class="k">if</span> <span class="nx">i</span> <span class="o">is</span> <span class="nx">@objects</span><span class="p">.</span><span class="nx">length</span> <span class="o">-</span> <span class="mi">1</span>
<span class="nx">objects</span><span class="p">.</span><span class="nx">push</span> <span class="nx">code</span>
<span class="k">else</span>
<span class="nx">objects</span><span class="p">.</span><span class="nx">push</span> <span class="s2">"$code, "</span>
<span class="nv">objects: </span><span class="nx">objects</span><span class="p">.</span><span class="nx">join</span><span class="p">(</span><span class="s1">''</span><span class="p">)</span>
<span class="k">if</span> <span class="nx">index_of</span><span class="p">(</span><span class="nx">objects</span><span class="p">,</span> <span class="s1">'\n'</span><span class="p">)</span> <span class="o">>=</span> <span class="mi">0</span>
<span class="s2">"[\n${@idt(1)}$objects\n$@tab]"</span>
<span class="k">else</span>
<span class="s2">"[$objects]"</span>
<span class="nx">children</span> <span class="nx">ArrayNode</span><span class="p">,</span> <span class="s1">'objects'</span></pre></div> </td> </tr> <tr id="section-74"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-74">#</a> </div> <h3>ClassNode</h3> </td> <td class="code"> <div class="highlight"><pre></pre></div> </td> </tr> <tr id="section-75"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-75">#</a> </div> <p>The CoffeeScript class definition.</p> </td> <td class="code"> <div class="highlight"><pre><span class="nv">exports.ClassNode: </span><span class="nx">class</span> <span class="nx">ClassNode</span> <span class="k">extends</span> <span class="nx">BaseNode</span></pre></div> </td> </tr> <tr id="section-76"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-76">#</a> </div> <p>Initialize a <strong>ClassNode</strong> with its name, an optional superclass, and a
list of prototype property assignments.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nv">constructor: </span><span class="p">(</span><span class="nx">variable</span><span class="p">,</span> <span class="nx">parent</span><span class="p">,</span> <span class="nx">props</span><span class="p">)</span> <span class="o">-></span>
<span class="vi">@variable: </span><span class="nx">variable</span>
<span class="vi">@parent: </span><span class="nx">parent</span>
<span class="vi">@properties: </span><span class="nx">props</span> <span class="o">or</span> <span class="p">[]</span>
<span class="vi">@returns: </span> <span class="kc">false</span>
<span class="nv">make_return: </span><span class="o">-></span>
<span class="vi">@returns: </span><span class="kc">true</span>
<span class="k">this</span></pre></div> </td> </tr> <tr id="section-77"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-77">#</a> </div> <p>Instead of generating the JavaScript string directly, we build up the
equivalent syntax tree and compile that, in pieces. You can see the
constructor, property assignments, and inheritance getting built out below.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nv">compile_node: </span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="o">-></span>
<span class="nv">extension: </span> <span class="nx">@parent</span> <span class="o">and</span> <span class="k">new</span> <span class="nx">ExtendsNode</span><span class="p">(</span><span class="nx">@variable</span><span class="p">,</span> <span class="nx">@parent</span><span class="p">)</span>
<span class="nv">constructor: </span><span class="kc">null</span>
<span class="nv">props: </span> <span class="k">new</span> <span class="nx">Expressions</span><span class="p">()</span>
<span class="nv">o.top: </span> <span class="kc">true</span>
<span class="k">for</span> <span class="nx">prop</span> <span class="k">in</span> <span class="nx">@properties</span>
<span class="p">[</span><span class="nx">pvar</span><span class="p">,</span> <span class="nx">func</span><span class="p">]</span><span class="o">:</span> <span class="p">[</span><span class="nx">prop</span><span class="p">.</span><span class="nx">variable</span><span class="p">,</span> <span class="nx">prop</span><span class="p">.</span><span class="nx">value</span><span class="p">]</span>
<span class="k">if</span> <span class="nx">pvar</span> <span class="o">and</span> <span class="nx">pvar</span><span class="p">.</span><span class="nx">base</span><span class="p">.</span><span class="nx">value</span> <span class="o">is</span> <span class="s1">'constructor'</span> <span class="o">and</span> <span class="nx">func</span> <span class="k">instanceof</span> <span class="nx">CodeNode</span>
<span class="nx">func</span><span class="p">.</span><span class="nx">body</span><span class="p">.</span><span class="nx">push</span><span class="p">(</span><span class="k">new</span> <span class="nx">ReturnNode</span><span class="p">(</span><span class="nx">literal</span><span class="p">(</span><span class="s1">'this'</span><span class="p">)))</span>
<span class="nv">constructor: </span><span class="k">new</span> <span class="nx">AssignNode</span><span class="p">(</span><span class="nx">@variable</span><span class="p">,</span> <span class="nx">func</span><span class="p">)</span>
<span class="k">else</span>
<span class="k">if</span> <span class="nx">pvar</span>
<span class="nv">access: </span><span class="k">if</span> <span class="nx">prop</span><span class="p">.</span><span class="nx">context</span> <span class="o">is</span> <span class="s1">'this'</span> <span class="k">then</span> <span class="nx">pvar</span><span class="p">.</span><span class="nx">base</span><span class="p">.</span><span class="nx">properties</span><span class="p">[</span><span class="mi">0</span><span class="p">]</span> <span class="k">else</span> <span class="k">new</span> <span class="nx">AccessorNode</span><span class="p">(</span><span class="nx">pvar</span><span class="p">,</span> <span class="s1">'prototype'</span><span class="p">)</span>
<span class="nv">val: </span> <span class="k">new</span> <span class="nx">ValueNode</span><span class="p">(</span><span class="nx">@variable</span><span class="p">,</span> <span class="p">[</span><span class="nx">access</span><span class="p">])</span>
<span class="nv">prop: </span> <span class="k">new</span> <span class="nx">AssignNode</span><span class="p">(</span><span class="nx">val</span><span class="p">,</span> <span class="nx">func</span><span class="p">)</span>
<span class="nx">props</span><span class="p">.</span><span class="nx">push</span> <span class="nx">prop</span>
<span class="nx">unless</span> <span class="nx">constructor</span>
<span class="k">if</span> <span class="nx">@parent</span>
<span class="nv">applied: </span><span class="k">new</span> <span class="nx">ValueNode</span><span class="p">(</span><span class="nx">@parent</span><span class="p">,</span> <span class="p">[</span><span class="k">new</span> <span class="nx">AccessorNode</span><span class="p">(</span><span class="nx">literal</span><span class="p">(</span><span class="s1">'apply'</span><span class="p">))])</span>
<span class="nv">constructor: </span><span class="k">new</span> <span class="nx">AssignNode</span><span class="p">(</span><span class="nx">@variable</span><span class="p">,</span> <span class="k">new</span> <span class="nx">CodeNode</span><span class="p">([],</span> <span class="k">new</span> <span class="nx">Expressions</span><span class="p">([</span>
<span class="k">new</span> <span class="nx">CallNode</span><span class="p">(</span><span class="nx">applied</span><span class="p">,</span> <span class="p">[</span><span class="nx">literal</span><span class="p">(</span><span class="s1">'this'</span><span class="p">),</span> <span class="nx">literal</span><span class="p">(</span><span class="s1">'arguments'</span><span class="p">)])</span>
<span class="p">])))</span>
<span class="k">else</span>
<span class="nv">constructor: </span><span class="k">new</span> <span class="nx">AssignNode</span><span class="p">(</span><span class="nx">@variable</span><span class="p">,</span> <span class="k">new</span> <span class="nx">CodeNode</span><span class="p">())</span>
<span class="nv">construct: </span> <span class="nx">@idt</span><span class="p">()</span> <span class="o">+</span> <span class="nx">constructor</span><span class="p">.</span><span class="nx">compile</span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="o">+</span> <span class="s1">';\n'</span>
<span class="nv">props: </span> <span class="k">if</span> <span class="nx">props</span><span class="p">.</span><span class="nx">empty</span><span class="p">()</span> <span class="k">then</span> <span class="s1">''</span> <span class="k">else</span> <span class="nx">props</span><span class="p">.</span><span class="nx">compile</span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="o">+</span> <span class="s1">'\n'</span>
<span class="nv">extension: </span><span class="k">if</span> <span class="nx">extension</span> <span class="k">then</span> <span class="nx">@idt</span><span class="p">()</span> <span class="o">+</span> <span class="nx">extension</span><span class="p">.</span><span class="nx">compile</span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="o">+</span> <span class="s1">';\n'</span> <span class="k">else</span> <span class="s1">''</span>
<span class="nv">returns: </span> <span class="k">if</span> <span class="nx">@returns</span> <span class="k">then</span> <span class="k">new</span> <span class="nx">ReturnNode</span><span class="p">(</span><span class="nx">@variable</span><span class="p">).</span><span class="nx">compile</span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="k">else</span> <span class="s1">''</span>
<span class="s2">"$construct$extension$props$returns"</span>
<span class="nx">statement</span> <span class="nx">ClassNode</span>
<span class="nx">children</span> <span class="nx">ClassNode</span><span class="p">,</span> <span class="s1">'variable'</span><span class="p">,</span> <span class="s1">'parent'</span><span class="p">,</span> <span class="s1">'properties'</span></pre></div> </td> </tr> <tr id="section-78"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-78">#</a> </div> <h3>AssignNode</h3> </td> <td class="code"> <div class="highlight"><pre></pre></div> </td> </tr> <tr id="section-79"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-79">#</a> </div> <p>The <strong>AssignNode</strong> is used to assign a local variable to value, or to set the
property of an object -- including within object literals.</p> </td> <td class="code"> <div class="highlight"><pre><span class="nv">exports.AssignNode: </span><span class="nx">class</span> <span class="nx">AssignNode</span> <span class="k">extends</span> <span class="nx">BaseNode</span></pre></div> </td> </tr> <tr id="section-80"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-80">#</a> </div> <p>Matchers for detecting prototype assignments.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nv">PROTO_ASSIGN: </span><span class="sr">/^(\S+)\.prototype/</span>
<span class="nv">LEADING_DOT: </span> <span class="sr">/^\.(prototype\.)?/</span>
<span class="nv">constructor: </span><span class="p">(</span><span class="nx">variable</span><span class="p">,</span> <span class="nx">value</span><span class="p">,</span> <span class="nx">context</span><span class="p">)</span> <span class="o">-></span>
<span class="vi">@variable: </span><span class="nx">variable</span>
<span class="vi">@value: </span><span class="nx">value</span>
<span class="vi">@context: </span><span class="nx">context</span>
<span class="nv">top_sensitive: </span><span class="o">-></span>
<span class="kc">true</span>
<span class="nv">is_value: </span><span class="o">-></span>
<span class="nx">@variable</span> <span class="k">instanceof</span> <span class="nx">ValueNode</span>
<span class="nv">make_return: </span><span class="o">-></span>
<span class="k">return</span> <span class="k">new</span> <span class="nx">Expressions</span> <span class="p">[</span><span class="k">this</span><span class="p">,</span> <span class="k">new</span> <span class="nx">ReturnNode</span><span class="p">(</span><span class="nx">@variable</span><span class="p">)]</span>
<span class="nv">is_statement: </span><span class="o">-></span>
<span class="nx">@is_value</span><span class="p">()</span> <span class="o">and</span> <span class="p">(</span><span class="nx">@variable</span><span class="p">.</span><span class="nx">is_array</span><span class="p">()</span> <span class="o">or</span> <span class="nx">@variable</span><span class="p">.</span><span class="nx">is_object</span><span class="p">())</span></pre></div> </td> </tr> <tr id="section-81"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-81">#</a> </div> <p>Compile an assignment, delegating to <code>compile_pattern_match</code> or
<code>compile_splice</code> if appropriate. Keep track of the name of the base object
we've been assigned to, for correct internal references. If the variable
has not been seen yet within the current scope, declare it.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nv">compile_node: </span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="o">-></span>
<span class="nv">top: </span> <span class="nx">del</span> <span class="nx">o</span><span class="p">,</span> <span class="s1">'top'</span>
<span class="k">return</span> <span class="nx">@compile_pattern_match</span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="k">if</span> <span class="nx">@is_statement</span><span class="p">()</span>
<span class="k">return</span> <span class="nx">@compile_splice</span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="k">if</span> <span class="nx">@is_value</span><span class="p">()</span> <span class="o">and</span> <span class="nx">@variable</span><span class="p">.</span><span class="nx">is_splice</span><span class="p">()</span>
<span class="nv">stmt: </span> <span class="nx">del</span> <span class="nx">o</span><span class="p">,</span> <span class="s1">'as_statement'</span>
<span class="nv">name: </span> <span class="nx">@variable</span><span class="p">.</span><span class="nx">compile</span><span class="p">(</span><span class="nx">o</span><span class="p">)</span>
<span class="nv">last: </span> <span class="k">if</span> <span class="nx">@is_value</span><span class="p">()</span> <span class="k">then</span> <span class="nx">@variable</span><span class="p">.</span><span class="nx">last</span><span class="p">.</span><span class="nx">replace</span><span class="p">(</span><span class="nx">@LEADING_DOT</span><span class="p">,</span> <span class="s1">''</span><span class="p">)</span> <span class="k">else</span> <span class="nx">name</span>
<span class="nv">match: </span> <span class="nx">name</span><span class="p">.</span><span class="nx">match</span><span class="p">(</span><span class="nx">@PROTO_ASSIGN</span><span class="p">)</span>
<span class="nv">proto: </span> <span class="nx">match</span> <span class="o">and</span> <span class="nx">match</span><span class="p">[</span><span class="mi">1</span><span class="p">]</span>
<span class="k">if</span> <span class="nx">@value</span> <span class="k">instanceof</span> <span class="nx">CodeNode</span>
<span class="vi">@value.name: </span> <span class="nx">last</span> <span class="k">if</span> <span class="nx">last</span><span class="p">.</span><span class="nx">match</span><span class="p">(</span><span class="nx">IDENTIFIER</span><span class="p">)</span>
<span class="vi">@value.proto: </span><span class="nx">proto</span> <span class="k">if</span> <span class="nx">proto</span>
<span class="nv">val: </span><span class="nx">@value</span><span class="p">.</span><span class="nx">compile</span> <span class="nx">o</span>
<span class="k">return</span> <span class="s2">"$name: $val"</span> <span class="k">if</span> <span class="nx">@context</span> <span class="o">is</span> <span class="s1">'object'</span>
<span class="nx">o</span><span class="p">.</span><span class="nx">scope</span><span class="p">.</span><span class="nx">find</span> <span class="nx">name</span> <span class="nx">unless</span> <span class="nx">@is_value</span><span class="p">()</span> <span class="o">and</span> <span class="nx">@variable</span><span class="p">.</span><span class="nx">has_properties</span><span class="p">()</span>
<span class="nv">val: </span><span class="s2">"$name = $val"</span>
<span class="k">return</span> <span class="s2">"$@tab$val;"</span> <span class="k">if</span> <span class="nx">stmt</span>
<span class="k">if</span> <span class="nx">top</span> <span class="k">then</span> <span class="nx">val</span> <span class="k">else</span> <span class="s2">"($val)"</span></pre></div> </td> </tr> <tr id="section-82"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-82">#</a> </div> <p>Brief implementation of recursive pattern matching, when assigning array or
object literals to a value. Peeks at their properties to assign inner names.
See the <a href="http://wiki.ecmascript.org/doku.php?id=harmony:destructuring">ECMAScript Harmony Wiki</a>
for details.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nv">compile_pattern_match: </span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="o">-></span>
<span class="nv">val_var: </span><span class="nx">o</span><span class="p">.</span><span class="nx">scope</span><span class="p">.</span><span class="nx">free_variable</span><span class="p">()</span>
<span class="nv">value: </span><span class="k">if</span> <span class="nx">@value</span><span class="p">.</span><span class="nx">is_statement</span><span class="p">()</span> <span class="k">then</span> <span class="nx">ClosureNode</span><span class="p">.</span><span class="nx">wrap</span><span class="p">(</span><span class="nx">@value</span><span class="p">)</span> <span class="k">else</span> <span class="nx">@value</span>
<span class="nv">assigns: </span><span class="p">[</span><span class="s2">"$@tab$val_var = ${ value.compile(o) };"</span><span class="p">]</span>
<span class="nv">o.top: </span><span class="kc">true</span>
<span class="nv">o.as_statement: </span><span class="kc">true</span>
<span class="nv">splat: </span><span class="kc">false</span>
<span class="k">for</span> <span class="nx">obj</span><span class="p">,</span> <span class="nx">i</span> <span class="k">in</span> <span class="nx">@variable</span><span class="p">.</span><span class="nx">base</span><span class="p">.</span><span class="nx">objects</span></pre></div> </td> </tr> <tr id="section-83"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-83">#</a> </div> <p>A regular array pattern-match.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nv">idx: </span><span class="nx">i</span>
<span class="k">if</span> <span class="nx">@variable</span><span class="p">.</span><span class="nx">is_object</span><span class="p">()</span>
<span class="k">if</span> <span class="nx">obj</span> <span class="k">instanceof</span> <span class="nx">AssignNode</span></pre></div> </td> </tr> <tr id="section-84"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-84">#</a> </div> <p>A regular object pattern-match.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="p">[</span><span class="nx">obj</span><span class="p">,</span> <span class="nx">idx</span><span class="p">]</span><span class="o">:</span> <span class="p">[</span><span class="nx">obj</span><span class="p">.</span><span class="nx">value</span><span class="p">,</span> <span class="nx">obj</span><span class="p">.</span><span class="nx">variable</span><span class="p">.</span><span class="nx">base</span><span class="p">]</span>
<span class="k">else</span></pre></div> </td> </tr> <tr id="section-85"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-85">#</a> </div> <p>A shorthand <code>{a, b, c}: val</code> pattern-match.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nv">idx: </span><span class="nx">obj</span>
<span class="k">if</span> <span class="o">not</span> <span class="p">(</span><span class="nx">obj</span> <span class="k">instanceof</span> <span class="nx">ValueNode</span> <span class="o">or</span> <span class="nx">obj</span> <span class="k">instanceof</span> <span class="nx">SplatNode</span><span class="p">)</span>
<span class="k">throw</span> <span class="k">new</span> <span class="nb">Error</span> <span class="s1">'pattern matching must use only identifiers on the left-hand side.'</span>
<span class="nv">is_string: </span><span class="nx">idx</span><span class="p">.</span><span class="nx">value</span> <span class="o">and</span> <span class="nx">idx</span><span class="p">.</span><span class="nx">value</span><span class="p">.</span><span class="nx">match</span> <span class="nx">IS_STRING</span>
<span class="nv">access_class: </span><span class="k">if</span> <span class="nx">is_string</span> <span class="o">or</span> <span class="nx">@variable</span><span class="p">.</span><span class="nx">is_array</span><span class="p">()</span> <span class="k">then</span> <span class="nx">IndexNode</span> <span class="k">else</span> <span class="nx">AccessorNode</span>
<span class="k">if</span> <span class="nx">obj</span> <span class="k">instanceof</span> <span class="nx">SplatNode</span> <span class="o">and</span> <span class="o">not</span> <span class="nx">splat</span>
<span class="nv">val: </span><span class="nx">literal</span><span class="p">(</span><span class="nx">obj</span><span class="p">.</span><span class="nx">compile_value</span><span class="p">(</span><span class="nx">o</span><span class="p">,</span> <span class="nx">val_var</span><span class="p">,</span>
<span class="p">(</span><span class="nv">oindex: </span><span class="nx">index_of</span><span class="p">(</span><span class="nx">@variable</span><span class="p">.</span><span class="nx">base</span><span class="p">.</span><span class="nx">objects</span><span class="p">,</span> <span class="nx">obj</span><span class="p">)),</span>
<span class="p">(</span><span class="nv">olength: </span><span class="nx">@variable</span><span class="p">.</span><span class="nx">base</span><span class="p">.</span><span class="nx">objects</span><span class="p">.</span><span class="nx">length</span><span class="p">)</span> <span class="o">-</span> <span class="nx">oindex</span> <span class="o">-</span> <span class="mi">1</span><span class="p">))</span>
<span class="nv">splat: </span><span class="kc">true</span>
<span class="k">else</span>
<span class="nv">idx: </span><span class="nx">literal</span><span class="p">(</span><span class="k">if</span> <span class="nx">splat</span> <span class="k">then</span> <span class="s2">"${val_var}.length - ${olength - idx}"</span> <span class="k">else</span> <span class="nx">idx</span><span class="p">)</span> <span class="k">if</span> <span class="k">typeof</span> <span class="nx">idx</span> <span class="o">isnt</span> <span class="s1">'object'</span>
<span class="nv">val: </span><span class="k">new</span> <span class="nx">ValueNode</span><span class="p">(</span><span class="nx">literal</span><span class="p">(</span><span class="nx">val_var</span><span class="p">),</span> <span class="p">[</span><span class="k">new</span> <span class="nx">access_class</span><span class="p">(</span><span class="nx">idx</span><span class="p">)])</span>
<span class="nx">assigns</span><span class="p">.</span><span class="nx">push</span><span class="p">(</span><span class="k">new</span> <span class="nx">AssignNode</span><span class="p">(</span><span class="nx">obj</span><span class="p">,</span> <span class="nx">val</span><span class="p">).</span><span class="nx">compile</span><span class="p">(</span><span class="nx">o</span><span class="p">))</span>
<span class="nv">code: </span><span class="nx">assigns</span><span class="p">.</span><span class="nx">join</span><span class="p">(</span><span class="s2">"\n"</span><span class="p">)</span>
<span class="nx">code</span></pre></div> </td> </tr> <tr id="section-86"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-86">#</a> </div> <p>Compile the assignment from an array splice literal, using JavaScript's
<code>Array#splice</code> method.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nv">compile_splice: </span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="o">-></span>
<span class="nv">name: </span> <span class="nx">@variable</span><span class="p">.</span><span class="nx">compile</span> <span class="nx">merge</span> <span class="nx">o</span><span class="p">,</span> <span class="p">{</span><span class="nv">only_first: </span><span class="kc">true</span><span class="p">}</span>
<span class="nv">l: </span> <span class="nx">@variable</span><span class="p">.</span><span class="nx">properties</span><span class="p">.</span><span class="nx">length</span>
<span class="nv">range: </span> <span class="nx">@variable</span><span class="p">.</span><span class="nx">properties</span><span class="p">[</span><span class="nx">l</span> <span class="o">-</span> <span class="mi">1</span><span class="p">].</span><span class="nx">range</span>
<span class="nv">plus: </span> <span class="k">if</span> <span class="nx">range</span><span class="p">.</span><span class="nx">exclusive</span> <span class="k">then</span> <span class="s1">''</span> <span class="k">else</span> <span class="s1">' + 1'</span>
<span class="nv">from: </span> <span class="nx">range</span><span class="p">.</span><span class="nx">from</span><span class="p">.</span><span class="nx">compile</span><span class="p">(</span><span class="nx">o</span><span class="p">)</span>
<span class="nv">to: </span> <span class="nx">range</span><span class="p">.</span><span class="nx">to</span><span class="p">.</span><span class="nx">compile</span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="o">+</span> <span class="s1">' - '</span> <span class="o">+</span> <span class="nx">from</span> <span class="o">+</span> <span class="nx">plus</span>
<span class="nv">val: </span> <span class="nx">@value</span><span class="p">.</span><span class="nx">compile</span><span class="p">(</span><span class="nx">o</span><span class="p">)</span>
<span class="s2">"${name}.splice.apply($name, [$from, $to].concat($val))"</span>
<span class="nx">children</span> <span class="nx">AssignNode</span><span class="p">,</span> <span class="s1">'variable'</span><span class="p">,</span> <span class="s1">'value'</span></pre></div> </td> </tr> <tr id="section-87"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-87">#</a> </div> <h3>CodeNode</h3> </td> <td class="code"> <div class="highlight"><pre></pre></div> </td> </tr> <tr id="section-88"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-88">#</a> </div> <p>A function definition. This is the only node that creates a new Scope.
When for the purposes of walking the contents of a function body, the CodeNode
has no <em>children</em> -- they're within the inner scope.</p> </td> <td class="code"> <div class="highlight"><pre><span class="nv">exports.CodeNode: </span><span class="nx">class</span> <span class="nx">CodeNode</span> <span class="k">extends</span> <span class="nx">BaseNode</span>
<span class="nv">constructor: </span><span class="p">(</span><span class="nx">params</span><span class="p">,</span> <span class="nx">body</span><span class="p">,</span> <span class="nx">tag</span><span class="p">)</span> <span class="o">-></span>
<span class="vi">@params: </span> <span class="nx">params</span> <span class="o">or</span> <span class="p">[]</span>
<span class="vi">@body: </span> <span class="nx">body</span> <span class="o">or</span> <span class="k">new</span> <span class="nx">Expressions</span><span class="p">()</span>
<span class="vi">@bound: </span> <span class="nx">tag</span> <span class="o">is</span> <span class="s1">'boundfunc'</span></pre></div> </td> </tr> <tr id="section-89"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-89">#</a> </div> <p>Compilation creates a new scope unless explicitly asked to share with the
outer scope. Handles splat parameters in the parameter list by peeking at
the JavaScript <code>arguments</code> objects. If the function is bound with the <code>=></code>
arrow, generates a wrapper that saves the current value of <code>this</code> through
a closure.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nv">compile_node: </span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="o">-></span>
<span class="nv">shared_scope: </span><span class="nx">del</span> <span class="nx">o</span><span class="p">,</span> <span class="s1">'shared_scope'</span>
<span class="nv">top: </span> <span class="nx">del</span> <span class="nx">o</span><span class="p">,</span> <span class="s1">'top'</span>
<span class="nv">o.scope: </span> <span class="nx">shared_scope</span> <span class="o">or</span> <span class="k">new</span> <span class="nx">Scope</span><span class="p">(</span><span class="nx">o</span><span class="p">.</span><span class="nx">scope</span><span class="p">,</span> <span class="nx">@body</span><span class="p">,</span> <span class="k">this</span><span class="p">)</span>
<span class="nv">o.top: </span> <span class="kc">true</span>
<span class="nv">o.indent: </span> <span class="nx">@idt</span><span class="p">(</span><span class="k">if</span> <span class="nx">@bound</span> <span class="k">then</span> <span class="mi">2</span> <span class="k">else</span> <span class="mi">1</span><span class="p">)</span>
<span class="nx">del</span> <span class="nx">o</span><span class="p">,</span> <span class="s1">'no_wrap'</span>
<span class="nx">del</span> <span class="nx">o</span><span class="p">,</span> <span class="s1">'globals'</span>
<span class="nv">i: </span><span class="mi">0</span>
<span class="nv">splat: </span><span class="kc">undefined</span>
<span class="nv">params: </span><span class="p">[]</span>
<span class="k">for</span> <span class="nx">param</span> <span class="k">in</span> <span class="nx">@params</span>
<span class="k">if</span> <span class="nx">param</span> <span class="k">instanceof</span> <span class="nx">SplatNode</span> <span class="o">and</span> <span class="o">not</span> <span class="nx">splat</span><span class="o">?</span>
<span class="nv">splat: </span><span class="nx">param</span>
<span class="nv">splat.index: </span><span class="nx">i</span>
<span class="nv">splat.trailings: </span><span class="p">[]</span>
<span class="nv">splat.arglength: </span><span class="nx">@params</span><span class="p">.</span><span class="nx">length</span>
<span class="nx">@body</span><span class="p">.</span><span class="nx">unshift</span><span class="p">(</span><span class="nx">splat</span><span class="p">)</span>
<span class="k">else</span> <span class="k">if</span> <span class="nx">splat</span><span class="o">?</span>
<span class="nx">splat</span><span class="p">.</span><span class="nx">trailings</span><span class="p">.</span><span class="nx">push</span><span class="p">(</span><span class="nx">param</span><span class="p">)</span>
<span class="k">else</span>
<span class="nx">params</span><span class="p">.</span><span class="nx">push</span><span class="p">(</span><span class="nx">param</span><span class="p">)</span>
<span class="nv">i: </span><span class="o">+</span> <span class="mi">1</span>
<span class="nv">params: </span><span class="p">(</span><span class="nx">param</span><span class="p">.</span><span class="nx">compile</span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="k">for</span> <span class="nx">param</span> <span class="k">in</span> <span class="nx">params</span><span class="p">)</span>
<span class="nx">@body</span><span class="p">.</span><span class="nx">make_return</span><span class="p">()</span>
<span class="p">(</span><span class="nx">o</span><span class="p">.</span><span class="nx">scope</span><span class="p">.</span><span class="nx">parameter</span><span class="p">(</span><span class="nx">param</span><span class="p">))</span> <span class="k">for</span> <span class="nx">param</span> <span class="k">in</span> <span class="nx">params</span>
<span class="nv">code: </span><span class="k">if</span> <span class="nx">@body</span><span class="p">.</span><span class="nx">expressions</span><span class="p">.</span><span class="nx">length</span> <span class="k">then</span> <span class="s2">"\n${ @body.compile_with_declarations(o) }\n"</span> <span class="k">else</span> <span class="s1">''</span>
<span class="nv">func: </span><span class="s2">"function(${ params.join(', ') }) {$code${@idt(if @bound then 1 else 0)}}"</span>
<span class="nv">func: </span><span class="s2">"($func)"</span> <span class="k">if</span> <span class="nx">top</span> <span class="o">and</span> <span class="o">not</span> <span class="nx">@bound</span>
<span class="k">return</span> <span class="nx">func</span> <span class="nx">unless</span> <span class="nx">@bound</span>
<span class="nx">utility</span> <span class="s1">'slice'</span>
<span class="nv">ref: </span><span class="k">new</span> <span class="nx">ValueNode</span> <span class="nx">literal</span> <span class="nx">utility</span> <span class="s1">'bind'</span>
<span class="p">(</span><span class="k">new</span> <span class="nx">CallNode</span> <span class="nx">ref</span><span class="p">,</span> <span class="p">[</span><span class="nx">literal</span><span class="p">(</span><span class="nx">func</span><span class="p">),</span> <span class="nx">literal</span><span class="p">(</span><span class="s1">'this'</span><span class="p">)]).</span><span class="nx">compile</span> <span class="nx">o</span>
<span class="nv">top_sensitive: </span><span class="o">-></span>
<span class="kc">true</span></pre></div> </td> </tr> <tr id="section-90"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-90">#</a> </div> <p>Short-circuit traverse<em>children method to prevent it from crossing scope boundaries
unless cross</em>scope is true</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nv">traverse_children: </span><span class="p">(</span><span class="nx">cross_scope</span><span class="p">,</span> <span class="nx">func</span><span class="p">)</span> <span class="o">-></span> <span class="k">super</span><span class="p">(</span><span class="nx">cross_scope</span><span class="p">,</span> <span class="nx">func</span><span class="p">)</span> <span class="k">if</span> <span class="nx">cross_scope</span>
<span class="nv">toString: </span><span class="p">(</span><span class="nx">idt</span><span class="p">)</span> <span class="o">-></span>
<span class="nv">idt: </span><span class="o">or</span> <span class="s1">''</span>
<span class="nv">children: </span><span class="p">(</span><span class="nx">child</span><span class="p">.</span><span class="nx">toString</span><span class="p">(</span><span class="nx">idt</span> <span class="o">+</span> <span class="nx">TAB</span><span class="p">)</span> <span class="k">for</span> <span class="nx">child</span> <span class="k">in</span> <span class="nx">@children</span><span class="p">()).</span><span class="nx">join</span><span class="p">(</span><span class="s1">''</span><span class="p">)</span>
<span class="s2">"\n$idt$children"</span>
<span class="nx">children</span> <span class="nx">CodeNode</span><span class="p">,</span> <span class="s1">'params'</span><span class="p">,</span> <span class="s1">'body'</span></pre></div> </td> </tr> <tr id="section-91"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-91">#</a> </div> <h3>SplatNode</h3> </td> <td class="code"> <div class="highlight"><pre></pre></div> </td> </tr> <tr id="section-92"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-92">#</a> </div> <p>A splat, either as a parameter to a function, an argument to a call,
or as part of a destructuring assignment.</p> </td> <td class="code"> <div class="highlight"><pre><span class="nv">exports.SplatNode: </span><span class="nx">class</span> <span class="nx">SplatNode</span> <span class="k">extends</span> <span class="nx">BaseNode</span>
<span class="nv">constructor: </span><span class="p">(</span><span class="nx">name</span><span class="p">)</span> <span class="o">-></span>
<span class="nv">name: </span><span class="nx">literal</span><span class="p">(</span><span class="nx">name</span><span class="p">)</span> <span class="nx">unless</span> <span class="nx">name</span><span class="p">.</span><span class="nx">compile</span>
<span class="vi">@name: </span><span class="nx">name</span>
<span class="nv">compile_node: </span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="o">-></span>
<span class="k">if</span> <span class="nx">@index</span><span class="o">?</span> <span class="k">then</span> <span class="nx">@compile_param</span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="k">else</span> <span class="nx">@name</span><span class="p">.</span><span class="nx">compile</span><span class="p">(</span><span class="nx">o</span><span class="p">)</span></pre></div> </td> </tr> <tr id="section-93"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-93">#</a> </div> <p>Compiling a parameter splat means recovering the parameters that succeed
the splat in the parameter list, by slicing the arguments object.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nv">compile_param: </span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="o">-></span>
<span class="nv">name: </span><span class="nx">@name</span><span class="p">.</span><span class="nx">compile</span><span class="p">(</span><span class="nx">o</span><span class="p">)</span>
<span class="nx">o</span><span class="p">.</span><span class="nx">scope</span><span class="p">.</span><span class="nx">find</span> <span class="nx">name</span>
<span class="nv">len: </span><span class="nx">o</span><span class="p">.</span><span class="nx">scope</span><span class="p">.</span><span class="nx">free_variable</span><span class="p">()</span>
<span class="nx">o</span><span class="p">.</span><span class="nx">scope</span><span class="p">.</span><span class="nx">assign</span> <span class="nx">len</span><span class="p">,</span> <span class="s2">"arguments.length"</span>
<span class="nv">variadic: </span><span class="nx">o</span><span class="p">.</span><span class="nx">scope</span><span class="p">.</span><span class="nx">free_variable</span><span class="p">()</span>
<span class="nx">o</span><span class="p">.</span><span class="nx">scope</span><span class="p">.</span><span class="nx">assign</span> <span class="nx">variadic</span><span class="p">,</span> <span class="s2">"$len >= $@arglength"</span>
<span class="k">for</span> <span class="nx">trailing</span><span class="p">,</span> <span class="nx">idx</span> <span class="k">in</span> <span class="nx">@trailings</span>
<span class="nv">pos: </span><span class="nx">@trailings</span><span class="p">.</span><span class="nx">length</span> <span class="o">-</span> <span class="nx">idx</span>
<span class="nx">o</span><span class="p">.</span><span class="nx">scope</span><span class="p">.</span><span class="nx">assign</span><span class="p">(</span><span class="nx">trailing</span><span class="p">.</span><span class="nx">compile</span><span class="p">(</span><span class="nx">o</span><span class="p">),</span> <span class="s2">"arguments[$variadic ? $len - $pos : ${@index + idx}]"</span><span class="p">)</span>
<span class="s2">"$name = ${utility('slice')}.call(arguments, $@index, $len - ${@trailings.length})"</span></pre></div> </td> </tr> <tr id="section-94"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-94">#</a> </div> <p>A compiling a splat as a destructuring assignment means slicing arguments
from the right-hand-side's corresponding array.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nv">compile_value: </span><span class="p">(</span><span class="nx">o</span><span class="p">,</span> <span class="nx">name</span><span class="p">,</span> <span class="nx">index</span><span class="p">,</span> <span class="nx">trailings</span><span class="p">)</span> <span class="o">-></span>
<span class="nv">trail: </span><span class="k">if</span> <span class="nx">trailings</span> <span class="k">then</span> <span class="s2">", ${name}.length - $trailings"</span> <span class="k">else</span> <span class="s1">''</span>
<span class="s2">"${utility 'slice'}.call($name, $index$trail)"</span></pre></div> </td> </tr> <tr id="section-95"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-95">#</a> </div> <p>Utility function that converts arbitrary number of elements, mixed with
splats, to a proper array</p> </td> <td class="code"> <div class="highlight"><pre> <span class="vi">@compile_mixed_array: </span><span class="p">(</span><span class="nx">list</span><span class="p">,</span> <span class="nx">o</span><span class="p">)</span> <span class="o">-></span>
<span class="nv">args: </span><span class="p">[]</span>
<span class="nv">i: </span><span class="mi">0</span>
<span class="k">for</span> <span class="nx">arg</span> <span class="k">in</span> <span class="nx">list</span>
<span class="nv">code: </span><span class="nx">arg</span><span class="p">.</span><span class="nx">compile</span> <span class="nx">o</span>
<span class="k">if</span> <span class="o">not</span> <span class="p">(</span><span class="nx">arg</span> <span class="k">instanceof</span> <span class="nx">SplatNode</span><span class="p">)</span>
<span class="nv">prev: </span><span class="nx">args</span><span class="p">[</span><span class="nx">i</span> <span class="o">-</span> <span class="mi">1</span><span class="p">]</span>
<span class="k">if</span> <span class="nx">i</span> <span class="o">is</span> <span class="mi">1</span> <span class="o">and</span> <span class="nx">prev</span><span class="p">.</span><span class="nx">substr</span><span class="p">(</span><span class="mi">0</span><span class="p">,</span> <span class="mi">1</span><span class="p">)</span> <span class="o">is</span> <span class="s1">'['</span> <span class="o">and</span> <span class="nx">prev</span><span class="p">.</span><span class="nx">substr</span><span class="p">(</span><span class="nx">prev</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="mi">1</span><span class="p">)</span> <span class="o">is</span> <span class="s1">']'</span>
<span class="nx">args</span><span class="p">[</span><span class="nx">i</span> <span class="o">-</span> <span class="mi">1</span><span class="p">]</span><span class="o">:</span> <span class="s2">"${prev.substr(0, prev.length - 1)}, $code]"</span>
<span class="k">continue</span>
<span class="k">else</span> <span class="k">if</span> <span class="nx">i</span> <span class="o">></span> <span class="mi">1</span> <span class="o">and</span> <span class="nx">prev</span><span class="p">.</span><span class="nx">substr</span><span class="p">(</span><span class="mi">0</span><span class="p">,</span> <span class="mi">9</span><span class="p">)</span> <span class="o">is</span> <span class="s1">'.concat(['</span> <span class="o">and</span> <span class="nx">prev</span><span class="p">.</span><span class="nx">substr</span><span class="p">(</span><span class="nx">prev</span><span class="p">.</span><span class="nx">length</span> <span class="o">-</span> <span class="mi">2</span><span class="p">,</span> <span class="mi">2</span><span class="p">)</span> <span class="o">is</span> <span class="s1">'])'</span>
<span class="nx">args</span><span class="p">[</span><span class="nx">i</span> <span class="o">-</span> <span class="mi">1</span><span class="p">]</span><span class="o">:</span> <span class="s2">"${prev.substr(0, prev.length - 2)}, $code])"</span>
<span class="k">continue</span>
<span class="k">else</span>
<span class="nv">code: </span><span class="s2">"[$code]"</span>
<span class="nx">args</span><span class="p">.</span><span class="nx">push</span><span class="p">(</span><span class="k">if</span> <span class="nx">i</span> <span class="o">is</span> <span class="mi">0</span> <span class="k">then</span> <span class="nx">code</span> <span class="k">else</span> <span class="s2">".concat($code)"</span><span class="p">)</span>
<span class="nv">i: </span><span class="o">+</span> <span class="mi">1</span>
<span class="nx">args</span><span class="p">.</span><span class="nx">join</span><span class="p">(</span><span class="s1">''</span><span class="p">)</span>
<span class="nx">children</span> <span class="nx">SplatNode</span><span class="p">,</span> <span class="s1">'name'</span></pre></div> </td> </tr> <tr id="section-96"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-96">#</a> </div> <h3>WhileNode</h3> </td> <td class="code"> <div class="highlight"><pre></pre></div> </td> </tr> <tr id="section-97"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-97">#</a> </div> <p>A while loop, the only sort of low-level loop exposed by CoffeeScript. From
it, all other loops can be manufactured. Useful in cases where you need more
flexibility or more speed than a comprehension can provide.</p> </td> <td class="code"> <div class="highlight"><pre><span class="nv">exports.WhileNode: </span><span class="nx">class</span> <span class="nx">WhileNode</span> <span class="k">extends</span> <span class="nx">BaseNode</span>
<span class="nv">constructor: </span><span class="p">(</span><span class="nx">condition</span><span class="p">,</span> <span class="nx">opts</span><span class="p">)</span> <span class="o">-></span>
<span class="k">if</span> <span class="nx">opts</span> <span class="o">and</span> <span class="nx">opts</span><span class="p">.</span><span class="nx">invert</span>
<span class="nv">condition: </span><span class="k">new</span> <span class="nx">ParentheticalNode</span> <span class="nx">condition</span> <span class="k">if</span> <span class="nx">condition</span> <span class="k">instanceof</span> <span class="nx">OpNode</span>
<span class="nv">condition: </span><span class="k">new</span> <span class="nx">OpNode</span><span class="p">(</span><span class="s1">'!'</span><span class="p">,</span> <span class="nx">condition</span><span class="p">)</span>
<span class="vi">@condition: </span><span class="nx">condition</span>
<span class="vi">@guard: </span><span class="nx">opts</span> <span class="o">and</span> <span class="nx">opts</span><span class="p">.</span><span class="nx">guard</span>
<span class="nv">add_body: </span><span class="p">(</span><span class="nx">body</span><span class="p">)</span> <span class="o">-></span>
<span class="vi">@body: </span><span class="nx">body</span>
<span class="k">this</span>
<span class="nv">make_return: </span><span class="o">-></span>
<span class="vi">@returns: </span><span class="kc">true</span>
<span class="k">this</span>
<span class="nv">top_sensitive: </span><span class="o">-></span>
<span class="kc">true</span></pre></div> </td> </tr> <tr id="section-98"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-98">#</a> </div> <p>The main difference from a JavaScript <em>while</em> is that the CoffeeScript
<em>while</em> can be used as a part of a larger expression -- while loops may
return an array containing the computed result of each iteration.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nv">compile_node: </span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="o">-></span>
<span class="nv">top: </span> <span class="nx">del</span><span class="p">(</span><span class="nx">o</span><span class="p">,</span> <span class="s1">'top'</span><span class="p">)</span> <span class="o">and</span> <span class="o">not</span> <span class="nx">@returns</span>
<span class="nv">o.indent: </span> <span class="nx">@idt</span> <span class="mi">1</span>
<span class="nv">o.top: </span> <span class="kc">true</span>
<span class="nv">cond: </span> <span class="nx">@condition</span><span class="p">.</span><span class="nx">compile</span><span class="p">(</span><span class="nx">o</span><span class="p">)</span>
<span class="nv">set: </span> <span class="s1">''</span>
<span class="nx">unless</span> <span class="nx">top</span>
<span class="nv">rvar: </span> <span class="nx">o</span><span class="p">.</span><span class="nx">scope</span><span class="p">.</span><span class="nx">free_variable</span><span class="p">()</span>
<span class="nv">set: </span> <span class="s2">"$@tab$rvar = [];\n"</span>
<span class="vi">@body: </span> <span class="nx">PushNode</span><span class="p">.</span><span class="nx">wrap</span><span class="p">(</span><span class="nx">rvar</span><span class="p">,</span> <span class="nx">@body</span><span class="p">)</span> <span class="k">if</span> <span class="nx">@body</span>
<span class="nv">pre: </span> <span class="s2">"$set${@tab}while ($cond)"</span>
<span class="vi">@body: </span> <span class="nx">Expressions</span><span class="p">.</span><span class="nx">wrap</span><span class="p">([</span><span class="k">new</span> <span class="nx">IfNode</span><span class="p">(</span><span class="nx">@guard</span><span class="p">,</span> <span class="nx">@body</span><span class="p">)])</span> <span class="k">if</span> <span class="nx">@guard</span>
<span class="k">if</span> <span class="nx">@returns</span>
<span class="nv">post: </span><span class="s1">'\n'</span> <span class="o">+</span> <span class="k">new</span> <span class="nx">ReturnNode</span><span class="p">(</span><span class="nx">literal</span><span class="p">(</span><span class="nx">rvar</span><span class="p">)).</span><span class="nx">compile</span><span class="p">(</span><span class="nx">merge</span><span class="p">(</span><span class="nx">o</span><span class="p">,</span> <span class="p">{</span><span class="nv">indent: </span><span class="nx">@idt</span><span class="p">()}))</span>
<span class="k">else</span>
<span class="nv">post: </span><span class="s1">''</span>
<span class="s2">"$pre {\n${ @body.compile(o) }\n$@tab}$post"</span>
<span class="nx">statement</span> <span class="nx">WhileNode</span>
<span class="nx">children</span> <span class="nx">WhileNode</span><span class="p">,</span> <span class="s1">'condition'</span><span class="p">,</span> <span class="s1">'guard'</span><span class="p">,</span> <span class="s1">'body'</span></pre></div> </td> </tr> <tr id="section-99"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-99">#</a> </div> <h3>OpNode</h3> </td> <td class="code"> <div class="highlight"><pre></pre></div> </td> </tr> <tr id="section-100"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-100">#</a> </div> <p>Simple Arithmetic and logical operations. Performs some conversion from
CoffeeScript operations into their JavaScript equivalents.</p> </td> <td class="code"> <div class="highlight"><pre><span class="nv">exports.OpNode: </span><span class="nx">class</span> <span class="nx">OpNode</span> <span class="k">extends</span> <span class="nx">BaseNode</span></pre></div> </td> </tr> <tr id="section-101"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-101">#</a> </div> <p>The map of conversions from CoffeeScript to JavaScript symbols.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nv">CONVERSIONS: </span><span class="p">{</span>
<span class="s1">'=='</span><span class="o">:</span> <span class="s1">'==='</span>
<span class="s1">'!='</span><span class="o">:</span> <span class="s1">'!=='</span>
<span class="p">}</span></pre></div> </td> </tr> <tr id="section-102"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-102">#</a> </div> <p>The list of operators for which we perform
<a href="http://docs.python.org/reference/expressions.html#notin">Python-style comparison chaining</a>.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nv">CHAINABLE: </span> <span class="p">[</span><span class="s1">'<'</span><span class="p">,</span> <span class="s1">'>'</span><span class="p">,</span> <span class="s1">'>='</span><span class="p">,</span> <span class="s1">'<='</span><span class="p">,</span> <span class="s1">'==='</span><span class="p">,</span> <span class="s1">'!=='</span><span class="p">]</span></pre></div> </td> </tr> <tr id="section-103"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-103">#</a> </div> <p>Our assignment operators that have no JavaScript equivalent.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nv">ASSIGNMENT: </span> <span class="p">[</span><span class="s1">'||='</span><span class="p">,</span> <span class="s1">'&&='</span><span class="p">,</span> <span class="s1">'?='</span><span class="p">]</span></pre></div> </td> </tr> <tr id="section-104"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-104">#</a> </div> <p>Operators must come before their operands with a space.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nv">PREFIX_OPERATORS: </span><span class="p">[</span><span class="s1">'typeof'</span><span class="p">,</span> <span class="s1">'delete'</span><span class="p">]</span>
<span class="nv">constructor: </span><span class="p">(</span><span class="nx">operator</span><span class="p">,</span> <span class="nx">first</span><span class="p">,</span> <span class="nx">second</span><span class="p">,</span> <span class="nx">flip</span><span class="p">)</span> <span class="o">-></span>
<span class="vi">@constructor.name: </span><span class="o">+</span> <span class="s1">' '</span> <span class="o">+</span> <span class="nx">operator</span>
<span class="vi">@first: </span><span class="nx">first</span>
<span class="vi">@second: </span><span class="nx">second</span>
<span class="vi">@operator: </span><span class="nx">@CONVERSIONS</span><span class="p">[</span><span class="nx">operator</span><span class="p">]</span> <span class="o">or</span> <span class="nx">operator</span>
<span class="vi">@flip: </span><span class="o">!!</span><span class="nx">flip</span>
<span class="nv">is_unary: </span><span class="o">-></span>
<span class="o">not</span> <span class="nx">@second</span>
<span class="nv">is_chainable: </span><span class="o">-></span>
<span class="nx">index_of</span><span class="p">(</span><span class="nx">@CHAINABLE</span><span class="p">,</span> <span class="nx">@operator</span><span class="p">)</span> <span class="o">>=</span> <span class="mi">0</span>
<span class="nv">compile_node: </span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="o">-></span>
<span class="nv">o.operation: </span><span class="kc">true</span>
<span class="k">return</span> <span class="nx">@compile_chain</span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="k">if</span> <span class="nx">@is_chainable</span><span class="p">()</span> <span class="o">and</span> <span class="nx">@first</span><span class="p">.</span><span class="nx">unwrap</span><span class="p">()</span> <span class="k">instanceof</span> <span class="nx">OpNode</span> <span class="o">and</span> <span class="nx">@first</span><span class="p">.</span><span class="nx">unwrap</span><span class="p">().</span><span class="nx">is_chainable</span><span class="p">()</span>
<span class="k">return</span> <span class="nx">@compile_assignment</span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="k">if</span> <span class="nx">index_of</span><span class="p">(</span><span class="nx">@ASSIGNMENT</span><span class="p">,</span> <span class="nx">@operator</span><span class="p">)</span> <span class="o">>=</span> <span class="mi">0</span>
<span class="k">return</span> <span class="nx">@compile_unary</span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="k">if</span> <span class="nx">@is_unary</span><span class="p">()</span>
<span class="k">return</span> <span class="nx">@compile_existence</span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="k">if</span> <span class="nx">@operator</span> <span class="o">is</span> <span class="s1">'?'</span>
<span class="p">[</span><span class="nx">@first</span><span class="p">.</span><span class="nx">compile</span><span class="p">(</span><span class="nx">o</span><span class="p">),</span> <span class="nx">@operator</span><span class="p">,</span> <span class="nx">@second</span><span class="p">.</span><span class="nx">compile</span><span class="p">(</span><span class="nx">o</span><span class="p">)].</span><span class="nx">join</span> <span class="s1">' '</span></pre></div> </td> </tr> <tr id="section-105"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-105">#</a> </div> <p>Mimic Python's chained comparisons when multiple comparison operators are
used sequentially. For example:</p>
<pre><code>bin/coffee -e "puts 50 < 65 > 10"
true
</code></pre> </td> <td class="code"> <div class="highlight"><pre> <span class="nv">compile_chain: </span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="o">-></span>
<span class="nv">shared: </span><span class="nx">@first</span><span class="p">.</span><span class="nx">unwrap</span><span class="p">().</span><span class="nx">second</span>
<span class="p">[</span><span class="nx">@first</span><span class="p">.</span><span class="nx">second</span><span class="p">,</span> <span class="nx">shared</span><span class="p">]</span><span class="o">:</span> <span class="nx">shared</span><span class="p">.</span><span class="nx">compile_reference</span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="k">if</span> <span class="nx">shared</span><span class="p">.</span><span class="nx">contains_type</span> <span class="nx">CallNode</span>
<span class="p">[</span><span class="nx">first</span><span class="p">,</span> <span class="nx">second</span><span class="p">,</span> <span class="nx">shared</span><span class="p">]</span><span class="o">:</span> <span class="p">[</span><span class="nx">@first</span><span class="p">.</span><span class="nx">compile</span><span class="p">(</span><span class="nx">o</span><span class="p">),</span> <span class="nx">@second</span><span class="p">.</span><span class="nx">compile</span><span class="p">(</span><span class="nx">o</span><span class="p">),</span> <span class="nx">shared</span><span class="p">.</span><span class="nx">compile</span><span class="p">(</span><span class="nx">o</span><span class="p">)]</span>
<span class="s2">"($first) && ($shared $@operator $second)"</span></pre></div> </td> </tr> <tr id="section-106"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-106">#</a> </div> <p>When compiling a conditional assignment, take care to ensure that the
operands are only evaluated once, even though we have to reference them
more than once.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nv">compile_assignment: </span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="o">-></span>
<span class="p">[</span><span class="nx">first</span><span class="p">,</span> <span class="nx">second</span><span class="p">]</span><span class="o">:</span> <span class="p">[</span><span class="nx">@first</span><span class="p">.</span><span class="nx">compile</span><span class="p">(</span><span class="nx">o</span><span class="p">),</span> <span class="nx">@second</span><span class="p">.</span><span class="nx">compile</span><span class="p">(</span><span class="nx">o</span><span class="p">)]</span>
<span class="nx">o</span><span class="p">.</span><span class="nx">scope</span><span class="p">.</span><span class="nx">find</span><span class="p">(</span><span class="nx">first</span><span class="p">)</span> <span class="k">if</span> <span class="nx">first</span><span class="p">.</span><span class="nx">match</span><span class="p">(</span><span class="nx">IDENTIFIER</span><span class="p">)</span>
<span class="k">return</span> <span class="s2">"$first = ${ ExistenceNode.compile_test(o, @first) } ? $first : $second"</span> <span class="k">if</span> <span class="nx">@operator</span> <span class="o">is</span> <span class="s1">'?='</span>
<span class="s2">"$first = $first ${ @operator.substr(0, 2) } $second"</span></pre></div> </td> </tr> <tr id="section-107"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-107">#</a> </div> <p>If this is an existence operator, we delegate to <code>ExistenceNode.compile_test</code>
to give us the safe references for the variables.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nv">compile_existence: </span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="o">-></span>
<span class="p">[</span><span class="nx">first</span><span class="p">,</span> <span class="nx">second</span><span class="p">]</span><span class="o">:</span> <span class="p">[</span><span class="nx">@first</span><span class="p">.</span><span class="nx">compile</span><span class="p">(</span><span class="nx">o</span><span class="p">),</span> <span class="nx">@second</span><span class="p">.</span><span class="nx">compile</span><span class="p">(</span><span class="nx">o</span><span class="p">)]</span>
<span class="nv">test: </span><span class="nx">ExistenceNode</span><span class="p">.</span><span class="nx">compile_test</span><span class="p">(</span><span class="nx">o</span><span class="p">,</span> <span class="nx">@first</span><span class="p">)</span>
<span class="s2">"$test ? $first : $second"</span></pre></div> </td> </tr> <tr id="section-108"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-108">#</a> </div> <p>Compile a unary <strong>OpNode</strong>.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nv">compile_unary: </span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="o">-></span>
<span class="nv">space: </span><span class="k">if</span> <span class="nx">index_of</span><span class="p">(</span><span class="nx">@PREFIX_OPERATORS</span><span class="p">,</span> <span class="nx">@operator</span><span class="p">)</span> <span class="o">>=</span> <span class="mi">0</span> <span class="k">then</span> <span class="s1">' '</span> <span class="k">else</span> <span class="s1">''</span>
<span class="nv">parts: </span><span class="p">[</span><span class="nx">@operator</span><span class="p">,</span> <span class="nx">space</span><span class="p">,</span> <span class="nx">@first</span><span class="p">.</span><span class="nx">compile</span><span class="p">(</span><span class="nx">o</span><span class="p">)]</span>
<span class="nv">parts: </span><span class="nx">parts</span><span class="p">.</span><span class="nx">reverse</span><span class="p">()</span> <span class="k">if</span> <span class="nx">@flip</span>
<span class="nx">parts</span><span class="p">.</span><span class="nx">join</span><span class="p">(</span><span class="s1">''</span><span class="p">)</span>
<span class="nx">children</span> <span class="nx">OpNode</span><span class="p">,</span> <span class="s1">'first'</span><span class="p">,</span> <span class="s1">'second'</span></pre></div> </td> </tr> <tr id="section-109"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-109">#</a> </div> <h3>TryNode</h3> </td> <td class="code"> <div class="highlight"><pre></pre></div> </td> </tr> <tr id="section-110"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-110">#</a> </div> <p>A classic <em>try/catch/finally</em> block.</p> </td> <td class="code"> <div class="highlight"><pre><span class="nv">exports.TryNode: </span><span class="nx">class</span> <span class="nx">TryNode</span> <span class="k">extends</span> <span class="nx">BaseNode</span>
<span class="nv">constructor: </span><span class="p">(</span><span class="nx">attempt</span><span class="p">,</span> <span class="nx">error</span><span class="p">,</span> <span class="nx">recovery</span><span class="p">,</span> <span class="nx">ensure</span><span class="p">)</span> <span class="o">-></span>
<span class="vi">@attempt: </span><span class="nx">attempt</span>
<span class="vi">@recovery: </span><span class="nx">recovery</span>
<span class="vi">@ensure: </span><span class="nx">ensure</span>
<span class="vi">@error: </span><span class="nx">error</span>
<span class="k">this</span>
<span class="nv">make_return: </span><span class="o">-></span>
<span class="vi">@attempt: </span><span class="nx">@attempt</span><span class="p">.</span><span class="nx">make_return</span><span class="p">()</span> <span class="k">if</span> <span class="nx">@attempt</span>
<span class="vi">@recovery: </span><span class="nx">@recovery</span><span class="p">.</span><span class="nx">make_return</span><span class="p">()</span> <span class="k">if</span> <span class="nx">@recovery</span>
<span class="k">this</span></pre></div> </td> </tr> <tr id="section-111"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-111">#</a> </div> <p>Compilation is more or less as you would expect -- the <em>finally</em> clause
is optional, the <em>catch</em> is not.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nv">compile_node: </span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="o">-></span>
<span class="nv">o.indent: </span> <span class="nx">@idt</span> <span class="mi">1</span>
<span class="nv">o.top: </span> <span class="kc">true</span>
<span class="nv">attempt_part: </span><span class="nx">@attempt</span><span class="p">.</span><span class="nx">compile</span><span class="p">(</span><span class="nx">o</span><span class="p">)</span>
<span class="nv">error_part: </span> <span class="k">if</span> <span class="nx">@error</span> <span class="k">then</span> <span class="s2">" (${ @error.compile(o) }) "</span> <span class="k">else</span> <span class="s1">' '</span>
<span class="nv">catch_part: </span> <span class="k">if</span> <span class="nx">@recovery</span> <span class="k">then</span> <span class="s2">" catch$error_part{\n${ @recovery.compile(o) }\n$@tab}"</span> <span class="k">else</span> <span class="s1">''</span>
<span class="nv">finally_part: </span><span class="p">(</span><span class="nx">@ensure</span> <span class="o">or</span> <span class="s1">''</span><span class="p">)</span> <span class="o">and</span> <span class="s1">' finally {\n'</span> <span class="o">+</span> <span class="nx">@ensure</span><span class="p">.</span><span class="nx">compile</span><span class="p">(</span><span class="nx">merge</span><span class="p">(</span><span class="nx">o</span><span class="p">))</span> <span class="o">+</span> <span class="s2">"\n$@tab}"</span>
<span class="s2">"${@tab}try {\n$attempt_part\n$@tab}$catch_part$finally_part"</span>
<span class="nx">statement</span> <span class="nx">TryNode</span>
<span class="nx">children</span> <span class="nx">TryNode</span><span class="p">,</span> <span class="s1">'attempt'</span><span class="p">,</span> <span class="s1">'recovery'</span><span class="p">,</span> <span class="s1">'ensure'</span></pre></div> </td> </tr> <tr id="section-112"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-112">#</a> </div> <h3>ThrowNode</h3> </td> <td class="code"> <div class="highlight"><pre></pre></div> </td> </tr> <tr id="section-113"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-113">#</a> </div> <p>Simple node to throw an exception.</p> </td> <td class="code"> <div class="highlight"><pre><span class="nv">exports.ThrowNode: </span><span class="nx">class</span> <span class="nx">ThrowNode</span> <span class="k">extends</span> <span class="nx">BaseNode</span>
<span class="nv">constructor: </span><span class="p">(</span><span class="nx">expression</span><span class="p">)</span> <span class="o">-></span>
<span class="vi">@expression: </span><span class="nx">expression</span></pre></div> </td> </tr> <tr id="section-114"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-114">#</a> </div> <p>A <strong>ThrowNode</strong> is already a return, of sorts...</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nv">make_return: </span><span class="o">-></span>
<span class="k">return</span> <span class="k">this</span>
<span class="nv">compile_node: </span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="o">-></span>
<span class="s2">"${@tab}throw ${@expression.compile(o)};"</span>
<span class="nx">statement</span> <span class="nx">ThrowNode</span>
<span class="nx">children</span> <span class="nx">ThrowNode</span><span class="p">,</span> <span class="s1">'expression'</span></pre></div> </td> </tr> <tr id="section-115"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-115">#</a> </div> <h3>ExistenceNode</h3> </td> <td class="code"> <div class="highlight"><pre></pre></div> </td> </tr> <tr id="section-116"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-116">#</a> </div> <p>Checks a variable for existence -- not <em>null</em> and not <em>undefined</em>. This is
similar to <code>.nil?</code> in Ruby, and avoids having to consult a JavaScript truth
table.</p> </td> <td class="code"> <div class="highlight"><pre><span class="nv">exports.ExistenceNode: </span><span class="nx">class</span> <span class="nx">ExistenceNode</span> <span class="k">extends</span> <span class="nx">BaseNode</span>
<span class="nv">constructor: </span><span class="p">(</span><span class="nx">expression</span><span class="p">)</span> <span class="o">-></span>
<span class="vi">@expression: </span><span class="nx">expression</span>
<span class="nv">compile_node: </span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="o">-></span>
<span class="nx">ExistenceNode</span><span class="p">.</span><span class="nx">compile_test</span><span class="p">(</span><span class="nx">o</span><span class="p">,</span> <span class="nx">@expression</span><span class="p">)</span></pre></div> </td> </tr> <tr id="section-117"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-117">#</a> </div> <p>The meat of the <strong>ExistenceNode</strong> is in this static <code>compile_test</code> method
because other nodes like to check the existence of their variables as well.
Be careful not to double-evaluate anything.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="vi">@compile_test: </span><span class="p">(</span><span class="nx">o</span><span class="p">,</span> <span class="nx">variable</span><span class="p">)</span> <span class="o">-></span>
<span class="p">[</span><span class="nx">first</span><span class="p">,</span> <span class="nx">second</span><span class="p">]</span><span class="o">:</span> <span class="p">[</span><span class="nx">variable</span><span class="p">,</span> <span class="nx">variable</span><span class="p">]</span>
<span class="k">if</span> <span class="nx">variable</span> <span class="k">instanceof</span> <span class="nx">CallNode</span> <span class="o">or</span> <span class="p">(</span><span class="nx">variable</span> <span class="k">instanceof</span> <span class="nx">ValueNode</span> <span class="o">and</span> <span class="nx">variable</span><span class="p">.</span><span class="nx">has_properties</span><span class="p">())</span>
<span class="p">[</span><span class="nx">first</span><span class="p">,</span> <span class="nx">second</span><span class="p">]</span><span class="o">:</span> <span class="nx">variable</span><span class="p">.</span><span class="nx">compile_reference</span><span class="p">(</span><span class="nx">o</span><span class="p">)</span>
<span class="p">[</span><span class="nx">first</span><span class="p">,</span> <span class="nx">second</span><span class="p">]</span><span class="o">:</span> <span class="p">[</span><span class="nx">first</span><span class="p">.</span><span class="nx">compile</span><span class="p">(</span><span class="nx">o</span><span class="p">),</span> <span class="nx">second</span><span class="p">.</span><span class="nx">compile</span><span class="p">(</span><span class="nx">o</span><span class="p">)]</span>
<span class="s2">"(typeof $first !== \"undefined\" && $second !== null)"</span>
<span class="nx">children</span> <span class="nx">ExistenceNode</span><span class="p">,</span> <span class="s1">'expression'</span></pre></div> </td> </tr> <tr id="section-118"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-118">#</a> </div> <h3>ParentheticalNode</h3> </td> <td class="code"> <div class="highlight"><pre></pre></div> </td> </tr> <tr id="section-119"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-119">#</a> </div> <p>An extra set of parentheses, specified explicitly in the source. At one time
we tried to clean up the results by detecting and removing redundant
parentheses, but no longer -- you can put in as many as you please.</p>
<p>Parentheses are a good way to force any statement to become an expression.</p> </td> <td class="code"> <div class="highlight"><pre><span class="nv">exports.ParentheticalNode: </span><span class="nx">class</span> <span class="nx">ParentheticalNode</span> <span class="k">extends</span> <span class="nx">BaseNode</span>
<span class="nv">constructor: </span><span class="p">(</span><span class="nx">expression</span><span class="p">)</span> <span class="o">-></span>
<span class="vi">@expression: </span><span class="nx">expression</span>
<span class="nv">is_statement: </span><span class="o">-></span>
<span class="nx">@expression</span><span class="p">.</span><span class="nx">is_statement</span><span class="p">()</span>
<span class="nv">make_return: </span><span class="o">-></span>
<span class="nx">@expression</span><span class="p">.</span><span class="nx">make_return</span><span class="p">()</span>
<span class="nv">compile_node: </span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="o">-></span>
<span class="nv">code: </span><span class="nx">@expression</span><span class="p">.</span><span class="nx">compile</span><span class="p">(</span><span class="nx">o</span><span class="p">)</span>
<span class="k">return</span> <span class="nx">code</span> <span class="k">if</span> <span class="nx">@is_statement</span><span class="p">()</span>
<span class="nv">l: </span> <span class="nx">code</span><span class="p">.</span><span class="nx">length</span>
<span class="nv">code: </span><span class="nx">code</span><span class="p">.</span><span class="nx">substr</span><span class="p">(</span><span class="nx">o</span><span class="p">,</span> <span class="nx">l</span><span class="o">-</span><span class="mi">1</span><span class="p">)</span> <span class="k">if</span> <span class="nx">code</span><span class="p">.</span><span class="nx">substr</span><span class="p">(</span><span class="nx">l</span><span class="o">-</span><span class="mi">1</span><span class="p">,</span> <span class="mi">1</span><span class="p">)</span> <span class="o">is</span> <span class="s1">';'</span>
<span class="k">if</span> <span class="nx">@expression</span> <span class="k">instanceof</span> <span class="nx">AssignNode</span> <span class="k">then</span> <span class="nx">code</span> <span class="k">else</span> <span class="s2">"($code)"</span>
<span class="nx">children</span> <span class="nx">ParentheticalNode</span><span class="p">,</span> <span class="s1">'expression'</span></pre></div> </td> </tr> <tr id="section-120"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-120">#</a> </div> <h3>ForNode</h3> </td> <td class="code"> <div class="highlight"><pre></pre></div> </td> </tr> <tr id="section-121"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-121">#</a> </div> <p>CoffeeScript's replacement for the <em>for</em> loop is our array and object
comprehensions, that compile into <em>for</em> loops here. They also act as an
expression, able to return the result of each filtered iteration.</p>
<p>Unlike Python array comprehensions, they can be multi-line, and you can pass
the current index of the loop as a second parameter. Unlike Ruby blocks,
you can map and filter in a single pass.</p> </td> <td class="code"> <div class="highlight"><pre><span class="nv">exports.ForNode: </span><span class="nx">class</span> <span class="nx">ForNode</span> <span class="k">extends</span> <span class="nx">BaseNode</span>
<span class="nv">constructor: </span><span class="p">(</span><span class="nx">body</span><span class="p">,</span> <span class="nx">source</span><span class="p">,</span> <span class="nx">name</span><span class="p">,</span> <span class="nx">index</span><span class="p">)</span> <span class="o">-></span>
<span class="vi">@body: </span> <span class="nx">body</span>
<span class="vi">@name: </span> <span class="nx">name</span>
<span class="vi">@index: </span> <span class="nx">index</span> <span class="o">or</span> <span class="kc">null</span>
<span class="vi">@source: </span> <span class="nx">source</span><span class="p">.</span><span class="nx">source</span>
<span class="vi">@guard: </span> <span class="nx">source</span><span class="p">.</span><span class="nx">guard</span>
<span class="vi">@step: </span> <span class="nx">source</span><span class="p">.</span><span class="nx">step</span>
<span class="vi">@object: </span> <span class="o">!!</span><span class="nx">source</span><span class="p">.</span><span class="nx">object</span>
<span class="p">[</span><span class="nx">@name</span><span class="p">,</span> <span class="nx">@index</span><span class="p">]</span><span class="o">:</span> <span class="p">[</span><span class="nx">@index</span><span class="p">,</span> <span class="nx">@name</span><span class="p">]</span> <span class="k">if</span> <span class="nx">@object</span>
<span class="vi">@pattern: </span><span class="nx">@name</span> <span class="k">instanceof</span> <span class="nx">ValueNode</span>
<span class="k">throw</span> <span class="k">new</span> <span class="nb">Error</span><span class="p">(</span><span class="s1">'index cannot be a pattern matching expression'</span><span class="p">)</span> <span class="k">if</span> <span class="nx">@index</span> <span class="k">instanceof</span> <span class="nx">ValueNode</span>
<span class="vi">@returns: </span><span class="kc">false</span>
<span class="nv">top_sensitive: </span><span class="o">-></span>
<span class="kc">true</span>
<span class="nv">make_return: </span><span class="o">-></span>
<span class="vi">@returns: </span><span class="kc">true</span>
<span class="k">this</span>
<span class="nv">compile_return_value: </span><span class="p">(</span><span class="nx">val</span><span class="p">,</span> <span class="nx">o</span><span class="p">)</span> <span class="o">-></span>
<span class="k">return</span> <span class="s1">'\n'</span> <span class="o">+</span> <span class="k">new</span> <span class="nx">ReturnNode</span><span class="p">(</span><span class="nx">literal</span><span class="p">(</span><span class="nx">val</span><span class="p">)).</span><span class="nx">compile</span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="k">if</span> <span class="nx">@returns</span>
<span class="k">return</span> <span class="s1">'\n'</span> <span class="o">+</span> <span class="nx">val</span> <span class="k">if</span> <span class="nx">val</span>
<span class="s1">''</span></pre></div> </td> </tr> <tr id="section-122"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-122">#</a> </div> <p>Welcome to the hairiest method in all of CoffeeScript. Handles the inner
loop, filtering, stepping, and result saving for array, object, and range
comprehensions. Some of the generated code can be shared in common, and
some cannot.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nv">compile_node: </span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="o">-></span>
<span class="nv">top_level: </span> <span class="nx">del</span><span class="p">(</span><span class="nx">o</span><span class="p">,</span> <span class="s1">'top'</span><span class="p">)</span> <span class="o">and</span> <span class="o">not</span> <span class="nx">@returns</span>
<span class="nv">range: </span> <span class="nx">@source</span> <span class="k">instanceof</span> <span class="nx">ValueNode</span> <span class="o">and</span> <span class="nx">@source</span><span class="p">.</span><span class="nx">base</span> <span class="k">instanceof</span> <span class="nx">RangeNode</span> <span class="o">and</span> <span class="o">not</span> <span class="nx">@source</span><span class="p">.</span><span class="nx">properties</span><span class="p">.</span><span class="nx">length</span>
<span class="nv">source: </span> <span class="k">if</span> <span class="nx">range</span> <span class="k">then</span> <span class="nx">@source</span><span class="p">.</span><span class="nx">base</span> <span class="k">else</span> <span class="nx">@source</span>
<span class="nv">scope: </span> <span class="nx">o</span><span class="p">.</span><span class="nx">scope</span>
<span class="nv">name: </span> <span class="nx">@name</span> <span class="o">and</span> <span class="nx">@name</span><span class="p">.</span><span class="nx">compile</span> <span class="nx">o</span>
<span class="nv">index: </span> <span class="nx">@index</span> <span class="o">and</span> <span class="nx">@index</span><span class="p">.</span><span class="nx">compile</span> <span class="nx">o</span>
<span class="nx">scope</span><span class="p">.</span><span class="nx">find</span> <span class="nx">name</span> <span class="k">if</span> <span class="nx">name</span> <span class="o">and</span> <span class="o">not</span> <span class="nx">@pattern</span>
<span class="nx">scope</span><span class="p">.</span><span class="nx">find</span> <span class="nx">index</span> <span class="k">if</span> <span class="nx">index</span>
<span class="nv">body_dent: </span> <span class="nx">@idt</span> <span class="mi">1</span>
<span class="nv">rvar: </span> <span class="nx">scope</span><span class="p">.</span><span class="nx">free_variable</span><span class="p">()</span> <span class="nx">unless</span> <span class="nx">top_level</span>
<span class="nv">ivar: </span> <span class="k">if</span> <span class="nx">range</span> <span class="k">then</span> <span class="nx">name</span> <span class="k">else</span> <span class="nx">index</span> <span class="o">or</span> <span class="nx">scope</span><span class="p">.</span><span class="nx">free_variable</span><span class="p">()</span>
<span class="nv">var_part: </span> <span class="s1">''</span>
<span class="nv">body: </span> <span class="nx">Expressions</span><span class="p">.</span><span class="nx">wrap</span><span class="p">([</span><span class="nx">@body</span><span class="p">])</span>
<span class="k">if</span> <span class="nx">range</span>
<span class="nv">source_part: </span> <span class="nx">source</span><span class="p">.</span><span class="nx">compile_variables</span> <span class="nx">o</span>
<span class="nv">for_part: </span> <span class="nx">source</span><span class="p">.</span><span class="nx">compile</span> <span class="nx">merge</span> <span class="nx">o</span><span class="p">,</span> <span class="p">{</span><span class="nv">index: </span><span class="nx">ivar</span><span class="p">,</span> <span class="nv">step: </span><span class="nx">@step</span><span class="p">}</span>
<span class="k">else</span>
<span class="nv">svar: </span> <span class="nx">scope</span><span class="p">.</span><span class="nx">free_variable</span><span class="p">()</span>
<span class="nv">source_part: </span> <span class="s2">"$svar = ${ @source.compile(o) };\n$@tab"</span>
<span class="k">if</span> <span class="nx">@pattern</span>
<span class="nv">var_part: </span> <span class="k">new</span> <span class="nx">AssignNode</span><span class="p">(</span><span class="nx">@name</span><span class="p">,</span> <span class="nx">literal</span><span class="p">(</span><span class="s2">"$svar[$ivar]"</span><span class="p">)).</span><span class="nx">compile</span><span class="p">(</span><span class="nx">merge</span> <span class="nx">o</span><span class="p">,</span> <span class="p">{</span><span class="nv">indent: </span><span class="nx">@idt</span><span class="p">(</span><span class="mi">1</span><span class="p">),</span> <span class="nv">top: </span><span class="kc">true</span><span class="p">})</span> <span class="o">+</span> <span class="s2">"\n"</span>
<span class="k">else</span>
<span class="nv">var_part: </span> <span class="s2">"$body_dent$name = $svar[$ivar];\n"</span> <span class="k">if</span> <span class="nx">name</span>
<span class="nx">unless</span> <span class="nx">@object</span>
<span class="nv">lvar: </span> <span class="nx">scope</span><span class="p">.</span><span class="nx">free_variable</span><span class="p">()</span>
<span class="nv">step_part: </span> <span class="k">if</span> <span class="nx">@step</span> <span class="k">then</span> <span class="s2">"$ivar += ${ @step.compile(o) }"</span> <span class="k">else</span> <span class="s2">"$ivar++"</span>
<span class="nv">for_part: </span> <span class="s2">"$ivar = 0, $lvar = ${svar}.length; $ivar < $lvar; $step_part"</span>
<span class="nv">set_result: </span> <span class="k">if</span> <span class="nx">rvar</span> <span class="k">then</span> <span class="nx">@idt</span><span class="p">()</span> <span class="o">+</span> <span class="nx">rvar</span> <span class="o">+</span> <span class="s1">' = []; '</span> <span class="k">else</span> <span class="nx">@idt</span><span class="p">()</span>
<span class="nv">return_result: </span> <span class="nx">@compile_return_value</span><span class="p">(</span><span class="nx">rvar</span><span class="p">,</span> <span class="nx">o</span><span class="p">)</span>
<span class="nv">body: </span> <span class="nx">ClosureNode</span><span class="p">.</span><span class="nx">wrap</span><span class="p">(</span><span class="nx">body</span><span class="p">,</span> <span class="kc">true</span><span class="p">)</span> <span class="k">if</span> <span class="nx">top_level</span> <span class="o">and</span> <span class="nx">body</span><span class="p">.</span><span class="nx">contains</span> <span class="p">(</span><span class="nx">n</span><span class="p">)</span> <span class="o">-></span> <span class="nx">n</span> <span class="k">instanceof</span> <span class="nx">CodeNode</span>
<span class="nv">body: </span> <span class="nx">PushNode</span><span class="p">.</span><span class="nx">wrap</span><span class="p">(</span><span class="nx">rvar</span><span class="p">,</span> <span class="nx">body</span><span class="p">)</span> <span class="nx">unless</span> <span class="nx">top_level</span>
<span class="k">if</span> <span class="nx">@guard</span>
<span class="nv">body: </span> <span class="nx">Expressions</span><span class="p">.</span><span class="nx">wrap</span><span class="p">([</span><span class="k">new</span> <span class="nx">IfNode</span><span class="p">(</span><span class="nx">@guard</span><span class="p">,</span> <span class="nx">body</span><span class="p">)])</span>
<span class="k">if</span> <span class="nx">@object</span>
<span class="nv">for_part: </span><span class="s2">"$ivar in $svar) { if (${utility('hasProp')}.call($svar, $ivar)"</span>
<span class="nv">body: </span> <span class="nx">body</span><span class="p">.</span><span class="nx">compile</span><span class="p">(</span><span class="nx">merge</span><span class="p">(</span><span class="nx">o</span><span class="p">,</span> <span class="p">{</span><span class="nv">indent: </span><span class="nx">body_dent</span><span class="p">,</span> <span class="nv">top: </span><span class="kc">true</span><span class="p">}))</span>
<span class="nv">vars: </span> <span class="k">if</span> <span class="nx">range</span> <span class="k">then</span> <span class="nx">name</span> <span class="k">else</span> <span class="s2">"$name, $ivar"</span>
<span class="nv">close: </span> <span class="k">if</span> <span class="nx">@object</span> <span class="k">then</span> <span class="s1">'}}'</span> <span class="k">else</span> <span class="s1">'}'</span>
<span class="s2">"$set_result${source_part}for ($for_part) {\n$var_part$body\n$@tab$close$return_result"</span>
<span class="nx">statement</span> <span class="nx">ForNode</span>
<span class="nx">children</span> <span class="nx">ForNode</span><span class="p">,</span> <span class="s1">'body'</span><span class="p">,</span> <span class="s1">'source'</span><span class="p">,</span> <span class="s1">'guard'</span></pre></div> </td> </tr> <tr id="section-123"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-123">#</a> </div> <h3>IfNode</h3> </td> <td class="code"> <div class="highlight"><pre></pre></div> </td> </tr> <tr id="section-124"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-124">#</a> </div> <p><em>If/else</em> statements. Our <em>switch/when</em> will be compiled into this. Acts as an
expression by pushing down requested returns to the last line of each clause.</p>
<p>Single-expression <strong>IfNodes</strong> are compiled into ternary operators if possible,
because ternaries are already proper expressions, and don't need conversion.</p> </td> <td class="code"> <div class="highlight"><pre><span class="nv">exports.IfNode: </span><span class="nx">class</span> <span class="nx">IfNode</span> <span class="k">extends</span> <span class="nx">BaseNode</span>
<span class="nv">constructor: </span><span class="p">(</span><span class="nx">condition</span><span class="p">,</span> <span class="nx">body</span><span class="p">,</span> <span class="nx">tags</span><span class="p">)</span> <span class="o">-></span>
<span class="vi">@condition: </span><span class="nx">condition</span>
<span class="vi">@body: </span> <span class="nx">body</span>
<span class="vi">@else_body: </span><span class="kc">null</span>
<span class="vi">@tags: </span> <span class="nx">tags</span> <span class="o">or</span> <span class="p">{}</span>
<span class="vi">@condition: </span><span class="k">new</span> <span class="nx">OpNode</span><span class="p">(</span><span class="s1">'!'</span><span class="p">,</span> <span class="k">new</span> <span class="nx">ParentheticalNode</span><span class="p">(</span><span class="nx">@condition</span><span class="p">))</span> <span class="k">if</span> <span class="nx">@tags</span><span class="p">.</span><span class="nx">invert</span>
<span class="vi">@is_chain: </span> <span class="kc">false</span>
<span class="nv">body_node: </span><span class="o">-></span> <span class="nx">@body</span><span class="o">?</span><span class="p">.</span><span class="nx">unwrap</span><span class="p">()</span>
<span class="nv">else_body_node: </span><span class="o">-></span> <span class="nx">@else_body</span><span class="o">?</span><span class="p">.</span><span class="nx">unwrap</span><span class="p">()</span>
<span class="nv">force_statement: </span><span class="o">-></span>
<span class="vi">@tags.statement: </span><span class="kc">true</span>
<span class="k">this</span></pre></div> </td> </tr> <tr id="section-125"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-125">#</a> </div> <p>Tag a chain of <strong>IfNodes</strong> with their object(s) to switch on for equality
tests. <code>rewrite_switch</code> will perform the actual change at compile time.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nv">switches_over: </span><span class="p">(</span><span class="nx">expression</span><span class="p">)</span> <span class="o">-></span>
<span class="vi">@switch_subject: </span><span class="nx">expression</span>
<span class="k">this</span></pre></div> </td> </tr> <tr id="section-126"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-126">#</a> </div> <p>Rewrite a chain of <strong>IfNodes</strong> with their switch condition for equality.
Ensure that the switch expression isn't evaluated more than once.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nv">rewrite_switch: </span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="o">-></span>
<span class="vi">@assigner: </span><span class="nx">@switch_subject</span>
<span class="nx">unless</span> <span class="p">(</span><span class="nx">@switch_subject</span><span class="p">.</span><span class="nx">unwrap</span><span class="p">()</span> <span class="k">instanceof</span> <span class="nx">LiteralNode</span><span class="p">)</span>
<span class="nv">variable: </span><span class="nx">literal</span><span class="p">(</span><span class="nx">o</span><span class="p">.</span><span class="nx">scope</span><span class="p">.</span><span class="nx">free_variable</span><span class="p">())</span>
<span class="vi">@assigner: </span><span class="k">new</span> <span class="nx">AssignNode</span><span class="p">(</span><span class="nx">variable</span><span class="p">,</span> <span class="nx">@switch_subject</span><span class="p">)</span>
<span class="vi">@switch_subject: </span><span class="nx">variable</span>
<span class="vi">@condition: </span><span class="k">for</span> <span class="nx">cond</span><span class="p">,</span> <span class="nx">i</span> <span class="k">in</span> <span class="nx">flatten</span> <span class="p">[</span><span class="nx">@condition</span><span class="p">]</span>
<span class="nv">cond: </span><span class="k">new</span> <span class="nx">ParentheticalNode</span><span class="p">(</span><span class="nx">cond</span><span class="p">)</span> <span class="k">if</span> <span class="nx">cond</span> <span class="k">instanceof</span> <span class="nx">OpNode</span>
<span class="k">new</span> <span class="nx">OpNode</span><span class="p">(</span><span class="s1">'=='</span><span class="p">,</span> <span class="p">(</span><span class="k">if</span> <span class="nx">i</span> <span class="o">is</span> <span class="mi">0</span> <span class="k">then</span> <span class="nx">@assigner</span> <span class="k">else</span> <span class="nx">@switch_subject</span><span class="p">),</span> <span class="nx">cond</span><span class="p">)</span>
<span class="nx">@else_body_node</span><span class="p">().</span><span class="nx">switches_over</span><span class="p">(</span><span class="nx">@switch_subject</span><span class="p">)</span> <span class="k">if</span> <span class="nx">@is_chain</span></pre></div> </td> </tr> <tr id="section-127"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-127">#</a> </div> <p>prevent this rewrite from happening again</p> </td> <td class="code"> <div class="highlight"><pre> <span class="vi">@switch_subject: </span><span class="kc">undefined</span>
<span class="k">this</span></pre></div> </td> </tr> <tr id="section-128"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-128">#</a> </div> <p>Rewrite a chain of <strong>IfNodes</strong> to add a default case as the final <em>else</em>.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nv">add_else: </span><span class="p">(</span><span class="nx">else_body</span><span class="p">,</span> <span class="nx">statement</span><span class="p">)</span> <span class="o">-></span>
<span class="k">if</span> <span class="nx">@is_chain</span>
<span class="nx">@else_body_node</span><span class="p">().</span><span class="nx">add_else</span> <span class="nx">else_body</span><span class="p">,</span> <span class="nx">statement</span>
<span class="k">else</span>
<span class="vi">@is_chain: </span><span class="nx">else_body</span> <span class="k">instanceof</span> <span class="nx">IfNode</span>
<span class="vi">@else_body: </span><span class="nx">@ensure_expressions</span> <span class="nx">else_body</span>
<span class="k">this</span></pre></div> </td> </tr> <tr id="section-129"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-129">#</a> </div> <p>The <strong>IfNode</strong> only compiles into a statement if either of its bodies needs
to be a statement. Otherwise a ternary is safe.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nv">is_statement: </span><span class="o">-></span>
<span class="vi">@statement: </span><span class="o">or</span> <span class="o">!!</span><span class="p">(</span><span class="nx">@comment</span> <span class="o">or</span> <span class="nx">@tags</span><span class="p">.</span><span class="nx">statement</span> <span class="o">or</span> <span class="nx">@body_node</span><span class="p">().</span><span class="nx">is_statement</span><span class="p">()</span> <span class="o">or</span> <span class="p">(</span><span class="nx">@else_body</span> <span class="o">and</span> <span class="nx">@else_body_node</span><span class="p">().</span><span class="nx">is_statement</span><span class="p">()))</span>
<span class="nv">compile_condition: </span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="o">-></span>
<span class="p">(</span><span class="nx">cond</span><span class="p">.</span><span class="nx">compile</span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="k">for</span> <span class="nx">cond</span> <span class="k">in</span> <span class="nx">flatten</span><span class="p">([</span><span class="nx">@condition</span><span class="p">])).</span><span class="nx">join</span><span class="p">(</span><span class="s1">' || '</span><span class="p">)</span>
<span class="nv">compile_node: </span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="o">-></span>
<span class="k">if</span> <span class="nx">@is_statement</span><span class="p">()</span> <span class="k">then</span> <span class="nx">@compile_statement</span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="k">else</span> <span class="nx">@compile_ternary</span><span class="p">(</span><span class="nx">o</span><span class="p">)</span>
<span class="nv">make_return: </span><span class="o">-></span>
<span class="vi">@body: </span> <span class="o">and</span> <span class="nx">@ensure_expressions</span><span class="p">(</span><span class="nx">@body</span><span class="p">.</span><span class="nx">make_return</span><span class="p">())</span>
<span class="vi">@else_body: </span><span class="o">and</span> <span class="nx">@ensure_expressions</span><span class="p">(</span><span class="nx">@else_body</span><span class="p">.</span><span class="nx">make_return</span><span class="p">())</span>
<span class="k">this</span>
<span class="nv">ensure_expressions: </span><span class="p">(</span><span class="nx">node</span><span class="p">)</span> <span class="o">-></span>
<span class="nv">node: </span><span class="k">new</span> <span class="nx">Expressions</span><span class="p">([</span><span class="nx">node</span><span class="p">])</span> <span class="nx">unless</span> <span class="nx">node</span> <span class="k">instanceof</span> <span class="nx">Expressions</span>
<span class="nx">node</span></pre></div> </td> </tr> <tr id="section-130"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-130">#</a> </div> <p>Compile the <strong>IfNode</strong> as a regular <em>if-else</em> statement. Flattened chains
force inner <em>else</em> bodies into statement form.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nv">compile_statement: </span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="o">-></span>
<span class="nx">@rewrite_switch</span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="k">if</span> <span class="nx">@switch_subject</span>
<span class="nv">child: </span> <span class="nx">del</span> <span class="nx">o</span><span class="p">,</span> <span class="s1">'chain_child'</span>
<span class="nv">cond_o: </span> <span class="nx">merge</span> <span class="nx">o</span>
<span class="nv">o.indent: </span> <span class="nx">@idt</span> <span class="mi">1</span>
<span class="nv">o.top: </span> <span class="kc">true</span>
<span class="nv">if_dent: </span> <span class="k">if</span> <span class="nx">child</span> <span class="k">then</span> <span class="s1">''</span> <span class="k">else</span> <span class="nx">@idt</span><span class="p">()</span>
<span class="nv">com_dent: </span> <span class="k">if</span> <span class="nx">child</span> <span class="k">then</span> <span class="nx">@idt</span><span class="p">()</span> <span class="k">else</span> <span class="s1">''</span>
<span class="nv">prefix: </span> <span class="k">if</span> <span class="nx">@comment</span> <span class="k">then</span> <span class="s2">"${ @comment.compile(cond_o) }\n$com_dent"</span> <span class="k">else</span> <span class="s1">''</span>
<span class="nv">body: </span> <span class="nx">@body</span><span class="p">.</span><span class="nx">compile</span><span class="p">(</span><span class="nx">o</span><span class="p">)</span>
<span class="nv">if_part: </span> <span class="s2">"$prefix${if_dent}if (${ @compile_condition(cond_o) }) {\n$body\n$@tab}"</span>
<span class="k">return</span> <span class="nx">if_part</span> <span class="nx">unless</span> <span class="nx">@else_body</span>
<span class="nv">else_part: </span><span class="k">if</span> <span class="nx">@is_chain</span>
<span class="s1">' else '</span> <span class="o">+</span> <span class="nx">@else_body_node</span><span class="p">().</span><span class="nx">compile</span><span class="p">(</span><span class="nx">merge</span><span class="p">(</span><span class="nx">o</span><span class="p">,</span> <span class="p">{</span><span class="nv">indent: </span><span class="nx">@idt</span><span class="p">(),</span> <span class="nv">chain_child: </span><span class="kc">true</span><span class="p">}))</span>
<span class="k">else</span>
<span class="s2">" else {\n${ @else_body.compile(o) }\n$@tab}"</span>
<span class="s2">"$if_part$else_part"</span></pre></div> </td> </tr> <tr id="section-131"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-131">#</a> </div> <p>Compile the IfNode as a ternary operator.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nv">compile_ternary: </span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="o">-></span>
<span class="nv">if_part: </span> <span class="nx">@condition</span><span class="p">.</span><span class="nx">compile</span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="o">+</span> <span class="s1">' ? '</span> <span class="o">+</span> <span class="nx">@body_node</span><span class="p">().</span><span class="nx">compile</span><span class="p">(</span><span class="nx">o</span><span class="p">)</span>
<span class="nv">else_part: </span> <span class="k">if</span> <span class="nx">@else_body</span> <span class="k">then</span> <span class="nx">@else_body_node</span><span class="p">().</span><span class="nx">compile</span><span class="p">(</span><span class="nx">o</span><span class="p">)</span> <span class="k">else</span> <span class="s1">'null'</span>
<span class="s2">"$if_part : $else_part"</span>
<span class="nx">children</span> <span class="nx">IfNode</span><span class="p">,</span> <span class="s1">'condition'</span><span class="p">,</span> <span class="s1">'body'</span><span class="p">,</span> <span class="s1">'else_body'</span><span class="p">,</span> <span class="s1">'assigner'</span></pre></div> </td> </tr> <tr id="section-132"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-132">#</a> </div> <h2>Faux-Nodes</h2> </td> <td class="code"> <div class="highlight"><pre></pre></div> </td> </tr> <tr id="section-133"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-133">#</a> </div> <h3>PushNode</h3> </td> <td class="code"> <div class="highlight"><pre></pre></div> </td> </tr> <tr id="section-134"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-134">#</a> </div> <p>Faux-nodes are never created by the grammar, but are used during code
generation to generate other combinations of nodes. The <strong>PushNode</strong> creates
the tree for <code>array.push(value)</code>, which is helpful for recording the result
arrays from comprehensions.</p> </td> <td class="code"> <div class="highlight"><pre><span class="nv">PushNode: exports.PushNode: </span><span class="p">{</span>
<span class="nv">wrap: </span><span class="p">(</span><span class="nx">array</span><span class="p">,</span> <span class="nx">expressions</span><span class="p">)</span> <span class="o">-></span>
<span class="nv">expr: </span><span class="nx">expressions</span><span class="p">.</span><span class="nx">unwrap</span><span class="p">()</span>
<span class="k">return</span> <span class="nx">expressions</span> <span class="k">if</span> <span class="nx">expr</span><span class="p">.</span><span class="nx">is_pure_statement</span><span class="p">()</span> <span class="o">or</span> <span class="nx">expr</span><span class="p">.</span><span class="nx">contains_pure_statement</span><span class="p">()</span>
<span class="nx">Expressions</span><span class="p">.</span><span class="nx">wrap</span><span class="p">([</span><span class="k">new</span> <span class="nx">CallNode</span><span class="p">(</span>
<span class="k">new</span> <span class="nx">ValueNode</span><span class="p">(</span><span class="nx">literal</span><span class="p">(</span><span class="nx">array</span><span class="p">),</span> <span class="p">[</span><span class="k">new</span> <span class="nx">AccessorNode</span><span class="p">(</span><span class="nx">literal</span><span class="p">(</span><span class="s1">'push'</span><span class="p">))]),</span> <span class="p">[</span><span class="nx">expr</span><span class="p">]</span>
<span class="p">)])</span>
<span class="p">}</span></pre></div> </td> </tr> <tr id="section-135"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-135">#</a> </div> <h3>ClosureNode</h3> </td> <td class="code"> <div class="highlight"><pre></pre></div> </td> </tr> <tr id="section-136"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-136">#</a> </div> <p>A faux-node used to wrap an expressions body in a closure.</p> </td> <td class="code"> <div class="highlight"><pre><span class="nv">ClosureNode: exports.ClosureNode: </span><span class="p">{</span></pre></div> </td> </tr> <tr id="section-137"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-137">#</a> </div> <p>Wrap the expressions body, unless it contains a pure statement,
in which case, no dice. If the body mentions <code>this</code> or <code>arguments</code>,
then make sure that the closure wrapper preserves the original values.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="nv">wrap: </span><span class="p">(</span><span class="nx">expressions</span><span class="p">,</span> <span class="nx">statement</span><span class="p">)</span> <span class="o">-></span>
<span class="k">return</span> <span class="nx">expressions</span> <span class="k">if</span> <span class="nx">expressions</span><span class="p">.</span><span class="nx">contains_pure_statement</span><span class="p">()</span>
<span class="nv">func: </span><span class="k">new</span> <span class="nx">ParentheticalNode</span><span class="p">(</span><span class="k">new</span> <span class="nx">CodeNode</span><span class="p">([],</span> <span class="nx">Expressions</span><span class="p">.</span><span class="nx">wrap</span><span class="p">([</span><span class="nx">expressions</span><span class="p">])))</span>
<span class="nv">args: </span><span class="p">[]</span>
<span class="nv">mentions_args: </span><span class="nx">expressions</span><span class="p">.</span><span class="nx">contains</span> <span class="p">(</span><span class="nx">n</span><span class="p">)</span> <span class="o">-></span> <span class="p">(</span><span class="nx">n</span> <span class="k">instanceof</span> <span class="nx">LiteralNode</span><span class="p">)</span> <span class="o">and</span> <span class="p">(</span><span class="nx">n</span><span class="p">.</span><span class="nx">value</span> <span class="o">is</span> <span class="s1">'arguments'</span><span class="p">)</span>
<span class="nv">mentions_this: </span><span class="nx">expressions</span><span class="p">.</span><span class="nx">contains</span> <span class="p">(</span><span class="nx">n</span><span class="p">)</span> <span class="o">-></span> <span class="p">(</span><span class="nx">n</span> <span class="k">instanceof</span> <span class="nx">LiteralNode</span><span class="p">)</span> <span class="o">and</span> <span class="p">(</span><span class="nx">n</span><span class="p">.</span><span class="nx">value</span> <span class="o">is</span> <span class="s1">'this'</span><span class="p">)</span>
<span class="k">if</span> <span class="nx">mentions_args</span> <span class="o">or</span> <span class="nx">mentions_this</span>
<span class="nv">meth: </span><span class="nx">literal</span><span class="p">(</span><span class="k">if</span> <span class="nx">mentions_args</span> <span class="k">then</span> <span class="s1">'apply'</span> <span class="k">else</span> <span class="s1">'call'</span><span class="p">)</span>
<span class="nv">args: </span><span class="p">[</span><span class="nx">literal</span><span class="p">(</span><span class="s1">'this'</span><span class="p">)]</span>
<span class="nx">args</span><span class="p">.</span><span class="nx">push</span> <span class="nx">literal</span> <span class="s1">'arguments'</span> <span class="k">if</span> <span class="nx">mentions_args</span>
<span class="nv">func: </span><span class="k">new</span> <span class="nx">ValueNode</span> <span class="nx">func</span><span class="p">,</span> <span class="p">[</span><span class="k">new</span> <span class="nx">AccessorNode</span><span class="p">(</span><span class="nx">meth</span><span class="p">)]</span>
<span class="nv">call: </span><span class="k">new</span> <span class="nx">CallNode</span><span class="p">(</span><span class="nx">func</span><span class="p">,</span> <span class="nx">args</span><span class="p">)</span>
<span class="k">if</span> <span class="nx">statement</span> <span class="k">then</span> <span class="nx">Expressions</span><span class="p">.</span><span class="nx">wrap</span><span class="p">([</span><span class="nx">call</span><span class="p">])</span> <span class="k">else</span> <span class="nx">call</span>
<span class="p">}</span></pre></div> </td> </tr> <tr id="section-138"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-138">#</a> </div> <h2>Utility Functions</h2> </td> <td class="code"> <div class="highlight"><pre><span class="nv">UTILITIES: </span><span class="p">{</span></pre></div> </td> </tr> <tr id="section-139"> <td class="docs"> <div class="octowrap"> <a class="octothorpe" href="#section-139">#</a> </div> <p>Correctly set up a prototype chain for inheritance, including a reference
to the superclass for <code>super()</code> calls. See: