Execute function for each array element in reverse

OSCC · JavaScript, Array · Oct 19, 2020

Executes a provided function once for each array element, starting from the array's last element.

• Use Array.prototype.slice() to clone the given array and Array.prototype.reverse() to reverse it.
• Use Array.prototype.forEach() to iterate over the reversed array.

const forEachRight = (arr, callback) =>
  arr
    .slice()
    .reverse()
    .forEach(callback);

forEachRight([1, 2, 3, 4], val => console.log(val)); // '4', '3', '2', '1'

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