case (elt === null) : res = true; break; 
case (elt === null) : res = true; break; 
function f4(arr){  var elt = '';  var res = false;  for (i=0; i<arr.length; i++)  {    elt = arr[i];    switch(true)    {      case (elt === null) :        res = true;        break;      default:        // do nothing    }  }  return res;}
5459	/local1/tlutelli/issta_data/temp/all_js/javascript/2007_temp/2007/5459/3703c3c05f398a63e55992f7687ef65273b26d6a/11.9.6-1.js/buggy/js/tests/ecma_3/Expressions/11.9.6-1.js