Самая производительная функция

const mostPerformant = (fns, iterations = 10000) => {
  const times = fns.map(fn => {
    const before = performance.now();
    for (let i = 0; i < iterations; i++) fn();
    return performance.now() - before;
  });
  return times.indexOf(Math.min(…times));
};
mostPerformant([
  () => {
    // Loops through the entire array before returning `false`
    [1, 2, 3, 4, 5, 6, 7, 8, 9, '10'].every(el => typeof el === 'number');
  },
  () => {
    // Only needs to reach index `1` before returning `false`
    [1, '2', 3, 4, 5, 6, 7, 8, 9, 10].every(el => typeof el === 'number');
  }
]); // 1
Функции JavaScript