for vs forEach (v119)

Revision 119 of this benchmark created on

Preparation HTML

<script src="https://ajax.googleapis.com/ajax/libs/jquery/1/jquery.min.js">
</script>

Setup

var i,
      value,
      length,
      values = [],
      sum = 0,
      context = values;
  
  
  for (i = 0; i < 10000; i++) {
      values[i] = Math.random();
  }
  
  function add(val) {
      sum += val;
  }
  
  function add2(key, val) {
      sum += val;
  }
  
  Array.prototype.loop = function (callback) {
   for (i = 0; i < this.length; i += 1) {
    callback(this[i]);
   }
  };
  Array.prototype.loop2 = function (callback) {
  var i = 0,
   l = this.length;
   for (; i < l; i += 1) {
    callback(this[i]);
   }
  };

Teardown



            i = 0;
  value = 0;
  length = 0;
  values = [];
  sum = 0;

Test runner

Ready to run.

Testing in
TestOps/sec
forEach
values.forEach(add);
ready
for loop, simple
for (i = 0; i < values.length; i++) {
    sum += values[i];
}
ready
for loop, cached length
length = values.length;
for (i = 0; i < length; i++) {
    sum += values[i];
}
ready
for loop, reverse
for (i = values.length - 1; i >= 0; i--) {
    sum += values[i];
}
ready
for loop, cached length, callback
length = values.length;
for (i = 0; i < length; i++) {
    add(values[i], i, values);
}
ready
for loop, cached length, callback.call
length = values.length;
for (i = 0; i < length; i++) {
    add.call(context, values[i], i, values);
}
ready
$.each
$.each(values, function(key, value) {
    sum += value;
});
ready
for ... in
for (i in values) {
    sum += values[i];
}
ready
for loop, reverse, decrement condition
for (i = values.length; i--;) {
    sum += values[i];
}
ready
for loop, reverse, pre-decrement
for (i = values.length - 1; i >= 0; --i) {
    sum += values[i];
}
ready
for loop, assignment condition
for (i = 0; (value = values[i]) !== undefined; i++) {
    sum += value;
}
ready
for loop, assignment condition, reversed
for (i = values.length - 1; (value = values[i]) !== undefined; i--) {
    sum += value;
}
ready
for loop, assignment condition, callback
for (i = 0; (value = values[i]) !== undefined; i++) {
    add(value, i, values);
}
ready
for loop, assignment condition, callback.call
for (i = 0; (value = values[i]) !== undefined; i++) {
    add.call(context, value, i, values);
}
ready
forEach2
values.forEach(add);
ready
asdf
for (i = 0; item = values[i]; ++i) {
    add(item);
}
ready
prototype loop
values.loop(add);
ready
$.each cached
$.each(values, add2);
ready
prototype loop 2
values.loop2(add);
ready

Revisions

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