for vs forEach

JavaScript performance comparison

Revision 220 of this test case created by

Preparation code

<script>
  var i, values = [],
      sum = 0;
  for (i = 0; i < 10000; i++) {
   values[i] = i;
  }
  
  function add(val) {
   sum += calc(val);
  }

  function calc(val) {
   return Math.sqrt(val) + Math.sqrt(val/7);
  }
</script>
    

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Testing in CCBot 2.0.0 / Other 0.0.0
Test Ops/sec
forEach
values.forEach(function(val, i) {
  add(val)
});
pending…
reduce
sum = values.reduce(function(prev, curr) {
  return calc(curr)
}, calc(values[0]));
pending…
every
values.every(function(val, i) {
  add(val);
  return true;
});
pending…
for+
var i = 0,
  max;

for (i = 0, max = values.length; i < max; i++) {
  add(values[i]);
}
pending…
for-
// preferred 1
var i;
for (i = values.length; i--;) {
  add(values[i]);
}
pending…
while
// preferred 2
var i = values.length;
while (i--) {
  add(values[i]);
}
pending…

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Revisions

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