JavaScript Event Debouncing

debounce.js

var ref = document.querySelector('#myDiv');

function foo() {
	console.log('hello');
}

function debounce(callback, time) {
	var timer = null;
	return function() {
		clearTimeout(timer);

		timer = setTimeout(function() {
				callback.call(null);
		}, time);
	}
}
//onscroll fires every time you scroll which is bad for performance
//debounce function delays the execution of the foo function.
//when you scroll continously, the callback foo function is called
//every 1s
ref.addEventListener('scroll', debounce(foo, 1000), false);