for vs forEach v2

JavaScript performance comparison

Revision 341 of this test case created by

Preparation code

<script src="https://ajax.googleapis.com/ajax/libs/jquery/1/jquery.min.js"></script>
<script>
  var i, values = [],
      sum = 0;
  for (i = 0; i < 10000; i++) {
   values[i] = i;
  }
  
  function add(val) {
   sum += val;
  }
</script>
      
<script>
Benchmark.prototype.setup = function() {
  function iterate(array, delegate) {
    var length = array.length;
    for (var i = 0; i < length; i++) {
      delegate(array[i]);
    }
  }

};
</script>

Preparation code output

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

Test runner

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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 (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…
for in
for (i in values) {
  add(values[i]);
}
pending…
jQuery's each method
$.each(values, function(index) {
  add(values[index]);
});
pending…
Custom iterator
//Custom iterator
Array.prototype.withAllDo = function(delegate) {
  var length = this.length;
  for (var i = 0; i < length; i++) {
    delegate(this[i]);
  }
};

values.withAllDo(add);
pending…
Iteration method
iterate(values, add);
pending…

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