explain any()

Mark Pilgrim · Mark Pilgrim · commit 5565d9cc7baf · 2010-09-20T10:59:59.000-04:00
diff --git a/special-method-names.html b/special-method-names.html
@@ -286,8 +286,8 @@ <h2 id=acts-like-set>Classes That Act Like Sets</h2>
 <a>        return len(self.keys())                             <span class=u>&#x2464;</span></a></code></pre>
 <ol>
 <li>Once you create an instance of the <code>cgi.FieldStorage</code> class, you can use the &#8220;<code>in</code>&#8221; operator to check whether a particular parameter was included in the query string.
-<li>The <code>__contains__()</code> method is the magic that makes this work.
-<li>When you say <code>if 'q' in fs</code>, Python looks for the <code>__contains__()</code> method on the <var>fs</var> object, which is defined in <code>cgi.py</code>. The value <code>'q'</code> is passed into the <code>__contains__()</code> method as the <var>key</var> argument.
+<li>The <code>__contains__()</code> method is the magic that makes this work. When you say <code>if 'q' in fs</code>, Python looks for the <code>__contains__()</code> method on the <var>fs</var> object, which is defined in <code>cgi.py</code>. The value <code>'q'</code> is passed into the <code>__contains__()</code> method as the <var>key</var> argument.
+<li>The <code>any()</code> function takes a <a href=advanced-iterators.html#generator-expressions>generator expression</a> and returns <code>True</code> if the generator spits out any items. The <code>any()</code> function is smart enough to stop as soon as the first match is found.
 <li>The same <code>FieldStorage</code> class also supports returning its length, so you can say <code>len(<var>fs</var>)</code> and it will call the <code>__len__()</code> method on the <code>FieldStorage</code> class to return the number of query parameters that it identified.
 <li>The <code>self.keys()</code> method checks whether <code>self.list is None</code>, so the <code>__len__</code> method doesn&#8217;t need to duplicate this error checking.
 </ol>
