For vs While

JavaScript performance comparison

Revision 34 of this test case created

Preparation code

<script>
  var i, values = [],
      sum = 0;
  for (i = 0; i < 10000; i++) {
   values[i] = i;
  }
  
  function add(val) {
   sum += val;
  }
</script>

Test runner

Warning! For accurate results, please disable Firebug before running the tests. (Why?)

Java applet disabled.

Testing in unknown unknown
Test Ops/sec
ForEach
 
values.forEach(add);
 pending…
for loop, simple
 
for (i = 0; i < values.length; i++) {
 add(values[i]);
}
 pending…
for loop, cached length
 
var len = values.length;
for (i = 0; i < len; i++) {
 add(values[i]);
}
 pending…
for loop, reverse
 
for (i = values.length - 1; i >= 0; i--) {
 add(values[i]);
}
 pending…
for loop, cached length, no callback
 
var len = values.length;
for (i = 0; i < len; i++) {
 sum += values[i];
}
 pending…
for loop, cached length, using function.call and supplying index and original array
 
var len = values.length;
for (i = 0; i < len; i++) {
 add.call(values, values[i], i, values);
}
 pending…
While, reversed + simple
 
var i = values.length;
while (--i >= 0) {
 sum += values[i];
}
 pending…
While, reversed + callback
 
var i = values.length;
while (--i >= 0) {
 add.call(values, values[i], i, values);
}
 pending…
while reversed without explicit comparison
 
var i = values.length;
while (--i) {
  sum += values[i];
}
 pending…

Compare results of other browsers

Revisions

You can edit these tests or add even more tests to this page by appending /edit to the URL. Here’s a list of current revisions for this page:

0 comments

Add a comment