<script language="javascript">

 // the string we are going to operate on
 var inputstr="this is my long test string with the word long in it; hope that the regular expression does not take too LONG.";

 // an empty string to hold the result
 var outputstr="";

 // our regular expression
 var regex=/long/gi;

 // run the regular expression to replace any match to our regular expression with the word short.
 outputstr=inputstr.replace(regex,"short");

 // pop up the string, which should be
 //"this is my short test string with the word short in it; hope that the regular expression does not take too short."
 alert(outputstr);

 </script>