Randomize arrays

shuffle.js

const shuffle = (arr, mixed = [], pool = arr.slice()) => {
  const remaining = pool.length;
  if (!remaining) return mixed;
  const index = Math.floor(Math.random() * remaining);
  const el = pool.splice(index, 1).pop();
  mixed.push(el);
  return shuffle(arr, mixed, pool);
};

Example:

shuffle(["Ben", "John", "Alex", "Tom"]); // => ["Alex", "Ben", "Tom", "John"]