3 ms·

Why use map instead of forEach?

• tvalentius 9y ago
  If you only want to translate(map) each element in to another set of value, using Map is much more simpler and readable than forEach
  • scottmf 9y ago
    The code loops through an array, has side effects and returns nothing so forEach would be more descriptive IMO. As for simple/readable it’s the same code but s/map/forEach.
  • grumblestumble 9y ago
    Actually, this is incorrect. You're abusing map here. The purpose of map is to map an existing array onto a new array. You're using map here to mutate properties on nodes in the original array, and creating a new Array, which has the length of the initial array, where each value is the return value of `node.style.background = 'yellow';` forEach is much more indicative of what you're actually doing here, which is running through an iterable and mutating properties on each node. Simple rule of thumb: if you're not using the results of `map`, you shouldn't be using it.