Fastest array loops in Javascript (v270)

Revision 270 of this benchmark created on

Preparation HTML

<script>
  // Populate the base array
  var arr = [];
  for( var i = 0; i < 1000; i++ ) {
    arr[i] = 'value' + i;
  }

  function someFn (ix) {
      return ix * 5 + 1 / 3 * 8;
  }
</script>

Test runner

Ready to run.

Testing in
TestOps/sec
For loop, basic
for( var i = 0; i < arr.length; i++ ) {
    someFn(i);
}
ready
While loop, basic
var i=0;
while(i < arr.length) {
    someFn(i);
    i++;
}
ready
For loop, cached
for (var i = 0, len = arr.length; i < len; i++) {
    someFn(i);
}
ready
For loop, i--
for (var i = arr.length; i > 0; i--) {
    someFn(i);
}
ready
forEach
arr.forEach(someFn);
ready
While loop, basic, cached, i+=1
var i = 0, l = arr.length;
while(i < l) {
    someFn(i);
    i += 1;
}
ready
While loop, basic, cached, i++
var i = 0, l = arr.length;
while(i < l) {
    someFn(i);
    i++;
}
ready

Revisions

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