caching length (v103)

Revision 103 of this benchmark created by Sampo Kivistö on

Setup

"use strict";
    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)
"use strict";
for (let i = 0; i < arr.length; i++) {
  arr[i] *= 2;
}
ready
cached length
"use strict";
for (let i = 0, len = arr.length; i < len; i++) {
  arr[i] *= 2;
}
ready
prefix increment
"use strict";
for (let i = 0; i < arr.length; ++i) {
  arr[i] *= 2;
}
ready
prefix increment + cached length
"use strict";
for (let i = 0, len = arr.length; i < len; ++i) {
  arr[i] *= 2;
}
ready
decrement
"use strict";
for (let i = arr.length - 1; i > -1; i--) {
  arr[i] *= 2;
}
ready
decrement without final-expression
"use strict";
for (let i = arr.length; i--;) {
   arr[i] *= 2;
}
ready
.forEach()
"use strict";
arr.forEach(function(element, i, array) {
 array[i] *= 2;
});
ready
for in
"use strict";
for(var i in arr) {
  arr[i] *= 2;
}
ready
.shift() (building new array)
"use strict";
var ar = [];

while (let dee = arr.shift()) {
  ar.push(dee * 2);
}
ready
while loop
"use strict";
let len = arr.length;
while (len--) {
  arr[len] *= 2;
}
ready

Revisions

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