Javascript for loop iteration notes

loop.js

const array = [1,2,3,4,5,6,7,8];
// Declarative looping example
array.forEach((x) => someFunction());
array.map((x) => someFunction());
array.reduce((x) => someFunction());

// Imperative looping
for (const a of array) {
  someFunction();
}
for (let i = 0; i < array.length; i++) {
  someFunction();
}
const len = array.length;
for (let i = 0; i < len; i++) {
  someFunction();
}

/*
  * Referenced from https://leanylabs.com/blog/js-forEach-map-reduce-vs-for-for_of/#arrayforeach-vs-for-and-forof
  * Looping using the declarative way is much slower than using the imperative way
  * For ... of loop and classic for loop have roughly same performance for arrays
  * Classic for can be expande to use temp element in it, but it doesn't have significance effect on performance
 */