for vs forEach

JavaScript performance comparison

Revision 512 of this test case created by

Preparation code

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

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Testing in CCBot 2.0.0 / Other 0.0.0
Test Ops/sec
forEach
values.forEach(add);
pending…
for loop, simple
for (var j = 0; j < values.length; j++) {
 add(values[j]);
}
pending…
for loop, cached length
var len = values.length;
for (var j = 0; j < len; j++) {
 add(values[j]);
}
pending…
for loop, reverse
for (var j = values.length - 1; j >= 0; j--) {
 add(values[j]);
}
pending…
forEach more local
(function() {
 var sum = 0;
 values.forEach(function(val) {
  sum += val;
 });
})();
pending…

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Revisions

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