title: Matching regex to start of input when starting at a specific posistion
body: <p>When using the RegExp in Javascript, if you want to match a regular expression to the start of input you can use ^ like this</p>
  
  <pre><code>var regEx = /^Zorg/g;  
  regExp.exec( "Zorg was here" );  // This is a match
  regExp.exec( "What is Zorg" );  // This is not a match
  </code></pre>
  
  <p>This does not work when starting the match in a different place in the string.</p>
  
  <pre><code>var regEx = /^Zorg/g;
  regExp.lastIndex = 5;
  regExp.exec( "What Zorg?" );  // This is not a match but i want it to
  </code></pre>
  
  <p>According to the mozilla documentation you should be able to make this a match by using the sticky flag y on the regExp.</p>
  
  <pre><code>var regEx = /^Zorg/gy;
  regExp.lastIndex = 5;
  regExp.exec( "What Zorg?" );  // This should match in firefox 
  </code></pre>
  
  <p>And now to the question. Is it possible to write a regular expression that matches at start of  search when starting on different index than 0.  (Using Node right now but want to make this work in webkit as well)</p>
  
  <pre><code>var regEx = ????;
  regExp.lastIndex = 5;
  regExp.exec( "What Zorg?" );  // This this should match 
  regExp.exec( "Who is Zorg?" );  // This this should not match
  </code></pre>