loop vs (v135)

Revision 135 of this benchmark created by Eric Perret on

Preparation HTML

<script>
  var arr = new Array(100);
  for(var i = 0; i < 100; i++) {
    arr[i] = "TEST";
  }
</script>

Test runner

Ready to run.

Testing in
TestOps/sec
while loop that imitates a for loop
var i = 0;
while (i < arr.length) {
  arr[i];
  i++;
};
ready
while loop that imitates a for loop, caching the length
var i = 0,
  len = arr.length;
while (i < len) {
  arr[i];
  i++;
};
ready
Reverse while loop
var i = arr.length;
while (i--) {
  arr[i];
};
ready
Reverse while loop without implicit ToBoolean
var i = arr.length;
while (i-- > 0) {
  arr[i];
};
ready
Reverse do … while loop
var i = arr.length;
do {
  arr[i];
} while (i--);
ready
Reverse for loop
for (var i = arr.length; i--;) {
  arr[i];
};
ready
Old ’n’ busted for loop
for (var i = 0; i < arr.length; ++i) {
  arr[i];
};
ready
Old ’n’ busted for loop, caching the length
for (var i = 0, len = arr.length; i < len; ++i) {
  arr[i];
};
ready
Cool guy loop
for (var i = -1; ++i < arr.length;) {
  arr[i];
};
ready
Cool guy loop, caching the length
for (var i = -1, len = arr.length; ++i < len;) {
  arr[i];
};
ready
Native Array#forEach implementation
arr.forEach(function(x) {
  x;
});
ready
Native Array#forEach implementation with named function
function foo(x) {
  x;
};
arr.forEach(foo);
ready
using for something in array
for (x in arr) {
  arr[x];
}
ready
Non-global for...in
for (var x in arr) {
  arr[x];
}
ready
cool guy loop post increment
for (var i = 0, l = arr.length; i++ < l;) {
  arr[i];
};
ready
for loop without length and array value assignment
for (var i = 0, value; value = arr[i++];) {
  value;
};
ready

Revisions

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