caching length (v78)

Revision 78 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
cached
for (var i = 0, len = arr.length; i < len; i++) {
  arr[i] *= 2;
}
ready
not cached
for (var i = 0; i < arr.length; i++) {
  arr[i] *= 2;
}
ready
Pre-loop cache
var i, len = arr.length; 
for (i=0; i < len; i++) {
  arr[i] *= 2;
}
ready
Cached !==
var i, len = arr.length; 
for (i=0; i !== len; i++) {
  arr[i] *= 2;
}
ready
do-while loop
var len = arr.length;
do {
  arr[len] *= 2;
} while (len--);
ready
Prefix Increment
for (var i = 0; i < arr.length; ++i) {
  arr[i] *= 2;
}
ready
Prefix + Cached
for (var i = 0, len = arr.length; i < len; ++i) {
  arr[i] *= 2;
}
ready
Array map
arr.map(function(el) {
  return el * 2;
});
ready
For in
for( var i in arr ) {
arr[i] *= 2;
}
ready

Revisions

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