for vs forEach vs while vs for..of (v293)

Revision 293 of this benchmark created by Maxime Warnier on


Description

Is it faster to use the native forEach or just loop with for? And how fast is while?

Preparation HTML

<script>
"use strict";
  var i, values = [],
      sum = 0;
  for (i = 0; i < 10000; i++) {
    values[i] = i;
  }

  function add(val) {
    sum += val;
  }
</script>

Test runner

Ready to run.

Testing in
TestOps/sec
forEach
values.forEach(add);
ready
for loop, simple
for (i = 0; i < values.length; i++) {
  add(values[i]);
}
ready
for loop, cached length
var len = values.length;
for (i = 0; i < len; i++) {
  add(values[i]);
}
ready
for loop, reverse
for (i = values.length - 1; i >= 0; i--) {
  add(values[i]);
}
ready
forEach more local
(function() {
  var sum = 0;
  values.forEach(function(val) {
    sum += val;
  });
})();
ready
for..int
for (var i in values) {
  add(values[i]);
}
ready
cached, in for
for (var i = 0, len = values.length; i < len; i++) {
  add(values[i]);
}
ready
while
i=0;
len=values.length
while (i++<len) {
  add(values[i]);
}
ready
while ++i
i=-1;
len=values.length;
while (++i<len) {
  add(values[i]);
}
ready
for cached with ++i
for (var i = 0, len = values.length; i < len; ++i) {
  add(values[i]);
}
ready
for with ++i
for (var i = 0; i < values.length; ++i) {
  add(values[i]);
}
ready
for of
for (var i of values) {
  add(i);
}
ready
for of with let
for (let i of values) {
  add(i);
}
ready

Revisions

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