title: What is the JavaScript equivalent of Ruby's "unless"?
body: <p>Ruby has a handy <a href="http://ruby-doc.org/docs/keywords/1.9/Object.html#method-i-unless" rel="noreferrer">unless</a> conditional, which is "The negative equivalent of if." </p>
  
  <p>Is there a way to do a "negative if" in JavaScript that's more semantic than <code>if (!condition)</code>?</p>