Loop vs map vs forEach

JavaScript performance comparison

Revision 10 of this test case created by canon and last updated

Preparation code


      
      <script>
Benchmark.prototype.setup = function() {
  var range = [];
  
  for (var i = 0; i < 10000; i++) {
    range.push({
      name: "value"
    }, {
      value: 5
    });
  }

};
</script>

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Testing in CCBot 2.0.0 / Other 0.0.0
Test Ops/sec
Loop different
var i,
  obj,
  item,
  ln = range.length,
  result = new Array(ln);

for (i = 0; i < ln; i++) {
  obj = {};
  item = range[i];
  obj[item.name] = item.value;
  result[i] = obj;
}
pending…
map
var result = range.map(function(item) {
  var obj = {};
  obj[item.name] = item.value;
  return obj;
});
pending…
forEach
var result = new Array(range.length),
  obj;

range.forEach(function(item, i) {
  obj = {};
  obj[item.name] = item.value;
  result[i] = obj;
});
pending…
Map modified
var result = new Array(range.length);
var obj;

range.map(function(item, i) {
  obj = {};
  obj[item.name] = item.value;
  result[i] = obj;
});
pending…
Loop popular
var result = [];

for (var i = 0; i < range.length; i++) {
  var obj = {}, item = range[i];
  obj[item.name] = item.value;
  result.push(obj);
}
pending…
while
var obj,
  item,
  ln = range.length,
  result = new Array(ln);

while (--ln > -1) {
  obj = {};
  item = range[ln];
  obj[item.name] = item.value;
  result[ln] = obj;
}
pending…

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Revisions

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