for vs forEach vs loop

JavaScript performance comparison

Revision 43 of this test case created

Info

added standard for loop to compare better

Preparation code

<script src="//cdnjs.cloudflare.com/ajax/libs/underscore.js/1.5.1/underscore-min.js"></script>
<script src="//cdnjs.cloudflare.com/ajax/libs/angular.js/1.1.5/angular.min.js"></script>
<script src="//cdnjs.cloudflare.com/ajax/libs/lodash.js/1.3.1/lodash.min.js"></script>
<script>
var lodash = _.noConflict();
</script>
<script>
Benchmark.prototype.setup = function() {
    var _ = window._,
       angular = window.angular,
       lodash = window.lodash;
   
    var arr = [];
    for(var i = 0; i < 100; i++) {
      arr[i] = {
        val: i,
        bool: Boolean((i % 3))
      };
    }
   
    var values = [];
};
</script>

Preparation code output

Test runner

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Testing in unknown unknown
Test Ops/sec
Array#forEach
arr.forEach(function(value) {
  if (value.bool) {
    values.push(value.val);
  }
});
pending…
underscore.forEach
_.forEach(arr, function(value) {
  if (value.bool) {
    values.push(value.val);
  }
});
pending…
lodash.forEach
lodash.forEach(arr, function(value) {
  if (value.bool) {
    values.push(value.val);
  }
});
pending…
angular.forEach
angular.forEach(arr, function(value) {
  if (value.bool) {
    values.push(value.val);
  }
});
pending…
standard for
for(var i = 0, l = arr.length; i < l; i++){
  if (arr[i].bool) {
    values.push( arr[i].val );
  }
}
pending…
standard for with caching
for(var i = 0, l = arr.length; i < l; i++){
  var itm = arr[i];
  if (itm.bool) {
    values.push( itm.val );
  }
}
pending…

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