js dom helpers

Короткий document.querySelector

function qs(selector, root) {
	return (root || document).querySelector(selector);
}

function qsa(selector, root) {
	return Array.prototype.slice.call((root || document).querySelectorAll(selector));
}

или так

const qs = (selector, root) => (root || document).querySelector(selector);
const qsa = (selector, root) => [...(root || document).querySelectorAll(selector)];

или так

const qs = (selector, root) => (root || document).querySelector(selector);
const qsa = (selector, root) => Array.from((root || document).querySelectorAll(selector));

пример использования

// один элемент
qs(".some-element");

// массив элементов
qsa(".some-elements").forEach(console.log);