> and other implementations provide this mechanism defined by the <a href="http://wiki.commonjs.org/wiki/CommonJS">CommonJS</a> group. For browsers this is provided by <a href="http://browserify.org">Browserify</a>, for instance.</p>

<H3><a name="Javascript_class_example"></a>26.4.2 Class</H3>


<p>The common example <code>class</code> defines three classes, <code>Shape</code>, <code>Circle</code>, and <code>Square</code>:</p>
<div class="code">
<pre>
class Shape {
public:
  Shape() {
    nshapes++;
  }
  