for and variable decralation

Benchmark created on

Setup

// Populate the base array
var arr = [];
for (var i = 0; i < 1000; i++) {
	arr[i] = i;
}
  
function someFn(i) {
	return i * 3 * 8;
}

Test runner

Ready to run.

Testing in
TestOps/sec
for outside let and length
let i;
let len = arr.length;
for (i = 0; i < len; i++) {
  someFn(arr[i]);
}
ready
for outside length
let len = arr.length;
for (let i = 0; i < len; i++) {
  someFn(arr[i]);
}
ready
for without length variable
for (let i = 0; i < arr.length; i++) {
  someFn(arr[i]);
}
ready
for
for (let i = 0, len = arr.length; i < len; i++) {
  someFn(arr[i]);
}
ready
for outside let
let i;
for (i = 0, len = arr.length; i < len; i++) {
  someFn(arr[i]);
}
ready
for-of outside let
let item;
for (item of arr) {
    someFn(item);
}
ready
for-of
for (let item of arr) {
    someFn(item);
}
ready
Array.forEach
arr.forEach(function (item){
  someFn(item);
})
ready

Revisions

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