for vs forEach (v330)

Revision 330 of this benchmark created by Paul West on

Description

Is it faster to use the native forEach or just loop with for?

Preparation HTML

<script>
  var i, values = [],
      sum = 0;
  for (i = 0; i < 10000; i++) {
   values[i] = i;
  }
  
  function add(val) {
   sum += val;
  }
</script>

Test runner

Ready to run.

Testing in
TestOps/sec
forEach
values.forEach(add);
ready
for loop, simple
for (i = 0; i < values.length; i++) {
 add(values[i]);
}
ready
for loop, cached length
var len = values.length;
for (i = 0; i < len; i++) {
 add(values[i]);
}
ready
for loop, reverse
for (i = values.length - 1; i >= 0; i--) {
 add(values[i]);
}
ready
forEach more local
(function() {
 var sum = 0;
 values.forEach(function(val) {
  sum += val;
 });
})();
ready
For loop, iteration variable
for( var i = 0, item; item = values[ i ]; i++ ){
  add( item );
}
ready

Revisions

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