Can't seem to understand this javascript code! if(!this.class)
<p>New to javascript here.</p>

<p>So I've been trying to learn to use Raphael.js and came across this <a href="http://jsfiddle.net/terryyounghk/AeU2r/" rel="nofollow">http://jsfiddle.net/terryyounghk/AeU2r/</a> snippet of code. </p>

<p>Now if you look at line 167, there is this "if" statement I just don't understand.</p>

<pre><code>   Raphael.el.style = function (state, style, aniOptions)
    {
     if (!this.class)
     {
        this.class = style ? style : 'default';
        this.aniOptions = aniOptions ? aniOptions : null;

        // start assigning some basic behaviors
        this.mouseover(function () { this.style('hover'); });
    .... 
</code></pre>

<p>What class? What is it returning? Who is returning it? </p>

<p>What is it even checking? That it's a class?</p>
