caching length (v101)

Revision 101 of this benchmark created on

Setup

var arr = [];
    for (var i = 0; i < 1000; i++) {
      arr[i] = Math.random();
    }

Test runner

Ready to run.

Testing in
TestOps/sec
not cached (basic)
for (var i = 0; i < arr.length; i++) {
  arr[i] *= 2;
}
ready
cached length
for (var i = 0, len = arr.length; i < len; i++) {
  arr[i] *= 2;
}
ready
prefix increment
for (var i = 0; i < arr.length; ++i) {
  arr[i] *= 2;
}
ready
prefix increment + cached length
for (var i = 0, len = arr.length; i < len; ++i) {
  arr[i] *= 2;
}
ready
decrement
for (var i = arr.length - 1; i > -1; i--) {
  arr[i] *= 2;
}
ready
decrement without final-expression
for (var i = arr.length; i--;) {
   arr[i] *= 2;
}
ready
.forEach()
arr.forEach(function(element, i, array) {
 array[i] *= 2;
});
ready
for in
for(var i in arr) {
  arr[i] *= 2;
}
ready
.shift() (building new array)
var el;
var ar = [];
while (el = arr.shift()) {
  ar.push(el * 2);
}
ready
while loop
var len = arr.length;
while (len--) {
  arr[len] *= 2;
}
ready

Revisions

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