EJ: C5 P4 created by oliverjam - https://repl.it/ETEO/2

EJ: C5 P4.js

function every(arr, f) {
	for (let i = 0; i < arr.length; i++) {
      if (!f(arr[i])) return false;
    }
	return true;
}

function some(arr, f) {
	for (let i = 0; i < arr.length; i++) {
		if (f(arr[i])) return true;
    }
	return false;
}

console.log(every([NaN, NaN, NaN], isNaN));
console.log(every([NaN, NaN, 4], isNaN));
console.log(some([NaN, 3, 4], isNaN));
console.log(some([2, 3, 4], isNaN));