"Static" class member 
<p>For example, <code>x</code> is <code>static</code> in class's definition. 
I should use <code>x</code> in this way:</p>

<p><code>class_name::x</code>; rather than <code>instance_of_class.x;</code></p>

<p>My question is, is the latter one also legal? Or just not correct?</p>

<p>Thanks.</p>
