Use 'new Function' instead of '(1, eval)'

In the hope that it'll be less confusing.
This commit is contained in:
Marijn Haverbeke 2012-10-12 23:09:23 +02:00
parent feaa7df563
commit 07152c41c4
2 changed files with 15 additions and 12 deletions

View File

@ -262,7 +262,7 @@
function makePredicate(words) {
words = words.split(" ");
var f = "(function(str){", cats = [];
var f = "", cats = [];
out: for (var i = 0; i < words.length; ++i) {
for (var j = 0; j < cats.length; ++j)
if (cats[j][0].length == words[i].length) {
@ -296,7 +296,7 @@
} else {
compareTo(words);
}
return (1, eval)(f + "})");
return new Function("str", f);
}
// The ECMAScript 3 reserved word list.

View File

@ -11,20 +11,21 @@ https://github.com/marijnh/acorn.git
</code></pre>
<p>Please use the <a href="https://github.com/marijnh/acorn/issues">github bug tracker</a> to report issues.</p> </td> <td class="code"> <div class="highlight"><pre><span class="p">(</span><span class="kd">function</span><span class="p">(</span><span class="nx">exports</span><span class="p">)</span> <span class="p">{</span>
<span class="s2">&quot;strict mode&quot;</span><span class="p">;</span>
<span class="s2">&quot;use strict&quot;</span><span class="p">;</span>
<span class="nx">exports</span><span class="p">.</span><span class="nx">version</span> <span class="o">=</span> <span class="s2">&quot;0.0.1&quot;</span><span class="p">;</span></pre></div> </td> </tr> <tr id="section-2"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-2">&#182;</a> </div> <p>The main exported interface (under <code>window.acorn</code> when in the
browser) is a <code>parse</code> function that takes a code string and
returns an abstract syntax tree as specified by <a href="https://developer.mozilla.org/en-US/docs/SpiderMonkey/Parser_API">Mozilla parser
API</a>, with the caveat that the SpiderMonkey-specific syntax
(<code>let</code>, <code>yield</code>, inline XML, etc) is not recognized.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="kd">var</span> <span class="nx">options</span><span class="p">,</span> <span class="nx">input</span><span class="p">,</span> <span class="nx">inputLen</span><span class="p">;</span>
(<code>let</code>, <code>yield</code>, inline XML, etc) is not recognized.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="kd">var</span> <span class="nx">options</span><span class="p">,</span> <span class="nx">input</span><span class="p">,</span> <span class="nx">inputLen</span><span class="p">,</span> <span class="nx">sourceFile</span><span class="p">;</span>
<span class="nx">exports</span><span class="p">.</span><span class="nx">parse</span> <span class="o">=</span> <span class="kd">function</span><span class="p">(</span><span class="nx">inpt</span><span class="p">,</span> <span class="nx">opts</span><span class="p">)</span> <span class="p">{</span>
<span class="nx">input</span> <span class="o">=</span> <span class="nb">String</span><span class="p">(</span><span class="nx">inpt</span><span class="p">);</span> <span class="nx">inputLen</span> <span class="o">=</span> <span class="nx">input</span><span class="p">.</span><span class="nx">length</span><span class="p">;</span>
<span class="nx">options</span> <span class="o">=</span> <span class="nx">opts</span> <span class="o">||</span> <span class="p">{};</span>
<span class="k">for</span> <span class="p">(</span><span class="kd">var</span> <span class="nx">opt</span> <span class="k">in</span> <span class="nx">defaultOptions</span><span class="p">)</span> <span class="k">if</span> <span class="p">(</span><span class="o">!</span><span class="nx">options</span><span class="p">.</span><span class="nx">hasOwnProperty</span><span class="p">(</span><span class="nx">opt</span><span class="p">))</span>
<span class="nx">options</span><span class="p">[</span><span class="nx">opt</span><span class="p">]</span> <span class="o">=</span> <span class="nx">defaultOptions</span><span class="p">[</span><span class="nx">opt</span><span class="p">];</span>
<span class="k">return</span> <span class="nx">parseTopLevel</span><span class="p">();</span>
<span class="nx">sourceFile</span> <span class="o">=</span> <span class="nx">options</span><span class="p">.</span><span class="nx">sourceFile</span> <span class="o">||</span> <span class="kc">null</span><span class="p">;</span>
<span class="k">return</span> <span class="nx">parseTopLevel</span><span class="p">(</span><span class="nx">options</span><span class="p">.</span><span class="nx">program</span><span class="p">);</span>
<span class="p">};</span></pre></div> </td> </tr> <tr id="section-3"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-3">&#182;</a> </div> <p>A second optional argument can be given to further configure
the parser process. These options are recognized:</p> </td> <td class="code"> <div class="highlight"><pre> <span class="kd">var</span> <span class="nx">defaultOptions</span> <span class="o">=</span> <span class="nx">exports</span><span class="p">.</span><span class="nx">defaultOptions</span> <span class="o">=</span> <span class="p">{</span></pre></div> </td> </tr> <tr id="section-4"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-4">&#182;</a> </div> <p><code>ecmaVersion</code> indicates the ECMAScript version to parse. Must
be either 3 or 5. This
@ -152,7 +153,7 @@ predicate from a space-separated string of words.</p>
<p>It starts by sorting the words by length.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="kd">function</span> <span class="nx">makePredicate</span><span class="p">(</span><span class="nx">words</span><span class="p">)</span> <span class="p">{</span>
<span class="nx">words</span> <span class="o">=</span> <span class="nx">words</span><span class="p">.</span><span class="nx">split</span><span class="p">(</span><span class="s2">&quot; &quot;</span><span class="p">);</span>
<span class="kd">var</span> <span class="nx">f</span> <span class="o">=</span> <span class="s2">&quot;(function(str){&quot;</span><span class="p">,</span> <span class="nx">cats</span> <span class="o">=</span> <span class="p">[];</span>
<span class="kd">var</span> <span class="nx">f</span> <span class="o">=</span> <span class="s2">&quot;&quot;</span><span class="p">,</span> <span class="nx">cats</span> <span class="o">=</span> <span class="p">[];</span>
<span class="nx">out</span><span class="o">:</span> <span class="k">for</span> <span class="p">(</span><span class="kd">var</span> <span class="nx">i</span> <span class="o">=</span> <span class="mi">0</span><span class="p">;</span> <span class="nx">i</span> <span class="o">&lt;</span> <span class="nx">words</span><span class="p">.</span><span class="nx">length</span><span class="p">;</span> <span class="o">++</span><span class="nx">i</span><span class="p">)</span> <span class="p">{</span>
<span class="k">for</span> <span class="p">(</span><span class="kd">var</span> <span class="nx">j</span> <span class="o">=</span> <span class="mi">0</span><span class="p">;</span> <span class="nx">j</span> <span class="o">&lt;</span> <span class="nx">cats</span><span class="p">.</span><span class="nx">length</span><span class="p">;</span> <span class="o">++</span><span class="nx">j</span><span class="p">)</span>
<span class="k">if</span> <span class="p">(</span><span class="nx">cats</span><span class="p">[</span><span class="nx">j</span><span class="p">][</span><span class="mi">0</span><span class="p">].</span><span class="nx">length</span> <span class="o">==</span> <span class="nx">words</span><span class="p">[</span><span class="nx">i</span><span class="p">].</span><span class="nx">length</span><span class="p">)</span> <span class="p">{</span>
@ -178,7 +179,7 @@ switch first dispatches on the lengths, to save on comparisons.</p>
<span class="nx">f</span> <span class="o">+=</span> <span class="s2">&quot;}&quot;</span><span class="p">;</span></pre></div> </td> </tr> <tr id="section-34"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-34">&#182;</a> </div> <p>Otherwise, simply generate a flat <code>switch</code> statement.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="p">}</span> <span class="k">else</span> <span class="p">{</span>
<span class="nx">compareTo</span><span class="p">(</span><span class="nx">words</span><span class="p">);</span>
<span class="p">}</span>
<span class="k">return</span> <span class="p">(</span><span class="mi">1</span><span class="p">,</span> <span class="nb">eval</span><span class="p">)(</span><span class="nx">f</span> <span class="o">+</span> <span class="s2">&quot;})&quot;</span><span class="p">);</span>
<span class="k">return</span> <span class="k">new</span> <span class="nb">Function</span><span class="p">(</span><span class="s2">&quot;str&quot;</span><span class="p">,</span> <span class="nx">f</span><span class="p">);</span>
<span class="p">}</span></pre></div> </td> </tr> <tr id="section-35"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-35">&#182;</a> </div> <p>The ECMAScript 3 reserved word list.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="kd">var</span> <span class="nx">isReservedWord3</span> <span class="o">=</span> <span class="nx">makePredicate</span><span class="p">(</span><span class="s2">&quot;abstract boolean byte char class double enum export extends final float goto implements import int interface long native package private protected public short static super synchronized throws transient volatile&quot;</span><span class="p">);</span></pre></div> </td> </tr> <tr id="section-36"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-36">&#182;</a> </div> <p>ECMAScript 5 reserved words.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="kd">var</span> <span class="nx">isReservedWord5</span> <span class="o">=</span> <span class="nx">makePredicate</span><span class="p">(</span><span class="s2">&quot;class enum extends super const export import&quot;</span><span class="p">);</span></pre></div> </td> </tr> <tr id="section-37"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-37">&#182;</a> </div> <p>The additional reserved words in strict mode.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="kd">var</span> <span class="nx">isStrictReservedWord</span> <span class="o">=</span> <span class="nx">makePredicate</span><span class="p">(</span><span class="s2">&quot;implements interface let package private protected public static yield&quot;</span><span class="p">);</span></pre></div> </td> </tr> <tr id="section-38"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-38">&#182;</a> </div> <p>The forbidden variable names in strict mode.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="kd">var</span> <span class="nx">isStrictBadIdWord</span> <span class="o">=</span> <span class="nx">makePredicate</span><span class="p">(</span><span class="s2">&quot;eval arguments&quot;</span><span class="p">);</span></pre></div> </td> </tr> <tr id="section-39"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-39">&#182;</a> </div> <p>And the keywords.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="kd">var</span> <span class="nx">isKeyword</span> <span class="o">=</span> <span class="nx">makePredicate</span><span class="p">(</span><span class="s2">&quot;break case catch continue debugger default do else finally for function if return switch throw try var while with null true false instanceof typeof void delete new in&quot;</span><span class="p">);</span></pre></div> </td> </tr> <tr id="section-40"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-40">&#182;</a> </div> <h2>Character categories</h2> </td> <td class="code"> <div class="highlight"><pre></pre></div> </td> </tr> <tr id="section-41"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-41">&#182;</a> </div> <p>Big ugly regular expressions that match characters in the
whitespace, identifier, and identifier-start categories. These
are only applied when a character is found to actually have a
@ -551,7 +552,7 @@ tests ("use strict"; 010; -- should fail).</p> </td> <td
<span class="nx">tokCommentsBefore</span> <span class="o">=</span> <span class="kc">null</span><span class="p">;</span>
<span class="p">}</span>
<span class="k">if</span> <span class="p">(</span><span class="nx">options</span><span class="p">.</span><span class="nx">locations</span><span class="p">)</span>
<span class="nx">node</span><span class="p">.</span><span class="nx">loc</span> <span class="o">=</span> <span class="p">{</span><span class="nx">start</span><span class="o">:</span> <span class="nx">tokStartLoc</span><span class="p">,</span> <span class="nx">end</span><span class="o">:</span> <span class="kc">null</span><span class="p">};</span>
<span class="nx">node</span><span class="p">.</span><span class="nx">loc</span> <span class="o">=</span> <span class="p">{</span><span class="nx">start</span><span class="o">:</span> <span class="nx">tokStartLoc</span><span class="p">,</span> <span class="nx">end</span><span class="o">:</span> <span class="kc">null</span><span class="p">,</span> <span class="nx">source</span><span class="o">:</span> <span class="nx">sourceFile</span><span class="p">};</span>
<span class="k">return</span> <span class="nx">node</span><span class="p">;</span>
<span class="p">}</span></pre></div> </td> </tr> <tr id="section-76"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-76">&#182;</a> </div> <p>Start a node whose start offset/comments information should be
based on the start of another node. For example, a binary
@ -563,7 +564,7 @@ already been parsed.</p> </td> <td class="code">
<span class="nx">other</span><span class="p">.</span><span class="nx">commentsBefore</span> <span class="o">=</span> <span class="kc">null</span><span class="p">;</span>
<span class="p">}</span>
<span class="k">if</span> <span class="p">(</span><span class="nx">options</span><span class="p">.</span><span class="nx">locations</span><span class="p">)</span>
<span class="nx">node</span><span class="p">.</span><span class="nx">loc</span> <span class="o">=</span> <span class="p">{</span><span class="nx">start</span><span class="o">:</span> <span class="nx">other</span><span class="p">.</span><span class="nx">loc</span><span class="p">.</span><span class="nx">start</span><span class="p">,</span> <span class="nx">end</span><span class="o">:</span> <span class="kc">null</span><span class="p">};</span>
<span class="nx">node</span><span class="p">.</span><span class="nx">loc</span> <span class="o">=</span> <span class="p">{</span><span class="nx">start</span><span class="o">:</span> <span class="nx">other</span><span class="p">.</span><span class="nx">loc</span><span class="p">.</span><span class="nx">start</span><span class="p">,</span> <span class="nx">end</span><span class="o">:</span> <span class="kc">null</span><span class="p">,</span> <span class="nx">source</span><span class="o">:</span> <span class="nx">other</span><span class="p">.</span><span class="nx">loc</span><span class="p">.</span><span class="nx">source</span><span class="p">};</span>
<span class="k">return</span> <span class="nx">node</span><span class="p">;</span>
<span class="p">}</span></pre></div> </td> </tr> <tr id="section-77"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-77">&#182;</a> </div> <p>Finish an AST node, adding <code>type</code>, <code>end</code>, and <code>commentsAfter</code>
@ -619,7 +620,9 @@ to.</p> </td> <td class="code"> <div class
<span class="k">if</span> <span class="p">(</span><span class="nx">strict</span> <span class="o">&amp;&amp;</span> <span class="nx">expr</span><span class="p">.</span><span class="nx">type</span> <span class="o">===</span> <span class="s2">&quot;Identifier&quot;</span> <span class="o">&amp;&amp;</span> <span class="nx">isStrictBadIdWord</span><span class="p">(</span><span class="nx">expr</span><span class="p">.</span><span class="nx">name</span><span class="p">))</span>
<span class="nx">raise</span><span class="p">(</span><span class="nx">expr</span><span class="p">.</span><span class="nx">start</span><span class="p">,</span> <span class="s2">&quot;Assigning to &quot;</span> <span class="o">+</span> <span class="nx">expr</span><span class="p">.</span><span class="nx">name</span> <span class="o">+</span> <span class="s2">&quot; in strict mode&quot;</span><span class="p">);</span>
<span class="p">}</span></pre></div> </td> </tr> <tr id="section-85"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-85">&#182;</a> </div> <h3>Statement parsing</h3> </td> <td class="code"> <div class="highlight"><pre></pre></div> </td> </tr> <tr id="section-86"> <td class="docs"> <div class="pilwrap"> <a class="pilcrow" href="#section-86">&#182;</a> </div> <p>Parse a program. Initializes the parser, reads any number of
statements, and wraps them in a Program node.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="kd">function</span> <span class="nx">parseTopLevel</span><span class="p">()</span> <span class="p">{</span>
statements, and wraps them in a Program node. Optionally takes a
<code>program</code> argument. If present, the statements will be appended
to its body instead of creating a new node.</p> </td> <td class="code"> <div class="highlight"><pre> <span class="kd">function</span> <span class="nx">parseTopLevel</span><span class="p">(</span><span class="nx">program</span><span class="p">)</span> <span class="p">{</span>
<span class="nx">initTokenState</span><span class="p">();</span>
<span class="nx">lastStart</span> <span class="o">=</span> <span class="nx">lastEnd</span> <span class="o">=</span> <span class="nx">tokPos</span><span class="p">;</span>
<span class="k">if</span> <span class="p">(</span><span class="nx">options</span><span class="p">.</span><span class="nx">locations</span><span class="p">)</span> <span class="nx">lastEndLoc</span> <span class="o">=</span> <span class="nx">curLineLoc</span><span class="p">();</span>
@ -627,8 +630,8 @@ statements, and wraps them in a Program node.</p> </td>
<span class="nx">labels</span> <span class="o">=</span> <span class="p">[];</span>
<span class="nx">readToken</span><span class="p">();</span>
<span class="kd">var</span> <span class="nx">node</span> <span class="o">=</span> <span class="nx">startNode</span><span class="p">(),</span> <span class="nx">first</span> <span class="o">=</span> <span class="kc">true</span><span class="p">;</span>
<span class="nx">node</span><span class="p">.</span><span class="nx">body</span> <span class="o">=</span> <span class="p">[];</span>
<span class="kd">var</span> <span class="nx">node</span> <span class="o">=</span> <span class="nx">program</span> <span class="o">||</span> <span class="nx">startNode</span><span class="p">(),</span> <span class="nx">first</span> <span class="o">=</span> <span class="kc">true</span><span class="p">;</span>
<span class="k">if</span> <span class="p">(</span><span class="o">!</span><span class="nx">program</span><span class="p">)</span> <span class="nx">node</span><span class="p">.</span><span class="nx">body</span> <span class="o">=</span> <span class="p">[];</span>
<span class="k">while</span> <span class="p">(</span><span class="nx">tokType</span> <span class="o">!==</span> <span class="nx">_eof</span><span class="p">)</span> <span class="p">{</span>
<span class="kd">var</span> <span class="nx">stmt</span> <span class="o">=</span> <span class="nx">parseStatement</span><span class="p">();</span>
<span class="nx">node</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="nx">stmt</span><span class="p">);</span>