Loop vs map vs forEach

JavaScript performance comparison

Revision 3 of this test case created by Blaise Kal

Info

Cache length in for loop

Preparation code

 
<script>
Benchmark.prototype.setup = function() {
    var range = [];
   
    for (var i = 0; i < 10000; i++) {
      range.push(i);
    }
};
</script>

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Testing in unknown unknown
Test Ops/sec
Loop
var result = [];

for (var i = 0, m = range.length; i < m; i++) {
  result.push(range[i] * 2);
}
pending…
Map
var result = range.map(function(val) {
  return val * 2;
});
pending…
forEach
var result = [];

range.forEach(function(val) {
  result.push(val * 2);
});
pending…

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