for vs forEach vs while vs Underscore.js (v345)

Revision 345 of this benchmark created by Asa on

Description

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

Preparation HTML

<script src="http://underscorejs.org/underscore-min.js"></script>
<script>
  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
var i;
for (i = 0; i < values.length; i++) {
  add(values[i]);
}
ready
for loop, cached length
var i, len = values.length;
for (i = 0; i < len; i++) {
  add(values[i]);
}
ready
for loop, reverse
var i;
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..in
var i;
for (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
while i-- with cached length
i = values.length;
while (i--) {
  add(values[i]);
}
ready
Underscore.js _.each
_(values).each(function(value) {
  add(value);
});
ready

Revisions

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