for vs forEach

JavaScript performance comparison

Revision 67 of this test case created

Info

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

Preparation code

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

  var eachElement = function(input, handler) {
    if (input !== undefined && input !== null) {
      for ( var i = input.length - 1; i >= 0; i--) {
        handler.apply(null, [input[i]]);
      }
    }
  };
</script>

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Testing in unknown unknown
Test Ops/sec
forEach
values.forEach(add);
pending…
for loop, simple
for (i = 0; i < values.length; i++) {
 add(values[i]);
}
pending…
for loop, cached length
var len = values.length;
for (i = 0; i < len; i++) {
 add(values[i]);
}
pending…
for loop, reverse
for (i = values.length - 1; i >= 0; i--) {
 add(values[i]);
}
pending…
eachElement
eachElement(values, add)
pending…

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