title: Stylus +cache not allowing formatted strings
body: <p>I don't understand why something like this occurs based off <a href="http://kizu.ru/en/issues/new-stylus-features/" rel="nofollow">this</a> article</p>
  
  <pre><code>+media(s("'(min-width: %spx)'", $max-padding)) // doesn't work
  +media('(max-width: ' + $max-padding + 'px)') // sloppy but works
  </code></pre>
  
  <p>The top compiles to the correct thing in the command line, but the +cache doesn't accept it</p>