DOM helpers

dom.js

/*
    What's better way to find a class match – `classes.indexOf(className)` or `for loop + return`?
*/

function hasClass(el, className) {
	var classes = el.className.split(' ');
	for (var i = 0; i < classes.length; i++) {
		if (classes[i] === className) {
			return true;
		}
	}
	return false;
}


function addClass(el, className) {
	var classes = el.className.split(' ');
	for (var i = 0; i < classes.length; i++) {
		if (classes[i] === className) {
			return;
		}
	}
	classes.push(className);
	el.className = classes.join(' ');
}


function removeClass(el, className) {
	// assume using our addClass, which excludes duplicate classes
	var classes = el.className.split(' ');
	for (var i = 0; i < classes.length; i++) {
		if (classes[i] === className) {
			break;
		}
	}
	classes.splice(i, 1);
	el.className = classes.join(' ');
}