var elements = document.querySelectorAll('div');
    callback = (el) => { console.log(el); };

// Spread operator
elements[Symbol.iterator]();
elements.forEach(callback) //[...elements].forEach(callback);

// Array.from()
Array.from(elements, callback) //Array.from(elements).forEach(callback);

// for...of statement
for (let div of elements) callback(div);