title: why is my indexOf statement creating an error
body: <p>I am trying to use .indexOf to find out if an array contains a string. Something is causing an error, but I don't know what. I'm sure this is a <strong>really</strong> simple thing, but I don't know the language and so don't see it. What's wrong?</p>
  
  <pre><code>//this code creates an error in IE
  var myMines=new Array();
  var newMine="22";
  var myVar = myMines.indexOf(newMine);   //when I comment out this line, the page does not generate an error
  </code></pre>