Caching Array Length

JavaScript performance comparison

Revision 29 of this test case created

Preparation code

Benchmark.prototype.setup = function() {
    var theArray = ["", 56,
      function() {},
      93, "lalala", {}
    var copyOfTheArray = [];

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Testing in unknown unknown
Test Ops/sec
With caching
var len = theArray.length;
for (var i = 0; i < len; i++) {
  copyOfTheArray[i] = theArray[i];
Without caching
for (var i = 0; i < theArray.length; i++) {
  copyOfTheArray[i] = theArray[i];

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