Is there a jQuery construct for "if (typeof someVar === 'undefined')"
<p>Does jQuery provide a way to to that test in a more concise way?</p>

<p><strong>Update</strong>
I should have left jQuery out of this.  It is just an issue of JavaScript.  It's been so long for me!  I am testing to see is something externally-defined module was loaded or not.  It appears that I can just use this instead:</p>

<pre><code>if (window.someVar)
</code></pre>

<p>Please correct me if this is a bad practice.  In my case, if someVar is defined, it will be an object.  It will not be defined to false.</p>
