Eliminating multiple OR conditions in JavaScript
<p>Any recommendations on the most efficient way to check if the value of a variable can be one of multiple values instead of trying use a long if condition concatenated with a bunch of || (ORs)?</p>

<p>I saw something like <code>if (value in {'thing1':1, 'thing2':1, 'thing3':1})</code> but I'm not entirely sure how it works. </p>

<p>What is <code>in</code> considered as? An operator?</p>
