title: JavaScript: Can ECMAScript 5's Strict Mode ("use strict") be enabled using single quotes ('use strict')?
body: <p>JavaScript doesn't care if your Strings are double-quoted <code>"double"</code> or single-quoted <code>'single'</code>.</p>
  
  <p>Every example of ECMAScript 5's strict mode has it enabled by <code>"use strict"</code> in double-quotes. Can I do the following (single-quotes):</p>
  
  <pre><code>alert(function(){
    'use strict';
    return !this;
  }());
  </code></pre>
  
  <p>This will return <em>true</em> if Strict mode is enabled, and <em>false</em> if it is not.</p>