(fixed) for vs forEach vs while

JavaScript performance comparison

Revision 319 of this test case created by

Preparation code

<script>
  var i, values = [],
      sum = 0;
  for (i = 0; i < 10; 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…
forEach more local
(function() {
  var sum = 0;
  values.forEach(function(val) {
    sum += val;
  });
})();
pending…
for..int
for (var i in values) {
  add(values[i]);
}
pending…
cached, in for
for (var i = 0, len = values.length; i < len; i++) {
  add(values[i]);
}
pending…
while
i=0;
len=values.length
while (i++<len) {
  add(values[i]);
}
pending…
while ++i
i=-1;
len=values.length;
while (++i<len) {
  add(values[i]);
}
pending…
for cached with ++i
for (var i = 0, len = values.length; i < len; ++i) {
  add(values[i]);
}
pending…
predecrement tweak
for (var i = 0, len = values.length; i < len; ++i) {
  add(values[i]);
}
pending…

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Revisions

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