JavaScript loops benchmark

Benchmark

https://jsben.ch/EAlKw

Result

Codes

Execute before every test

var arr = Array(1000000).fill(null)
var dosmth

for - Uncached length

for (let i = 0; i < arr.length; i++) {
  dosmth = arr[i]
}

for - Cached length

let len = arr.length
for (let i = 0; i < len; i++) {
  dosmth = arr[i]
}

for.. of

for (let val of arr) {
  dosmth = val
}

while - Uncached length

let i = 0

while (i < arr.length) {
  dosmth = arr[i]
  ++i
}

while - Cached length

let i = 0
const len = arr.length

while (i < len) {
  dosmth = arr[i]
  ++i
}

forEach

arr.forEach(el => (dosmth = el))

map

arr.map(el => (dosmth = el))