metavoid

(function (win, body) {
	win.RTCPeerConnection = win.RTCPeerConnection || win.mozRTCPeerConnection || win.webkitRTCPeerConnection;
	var rtc = new win.RTCPeerConnection();
	rtc.createDataChannel('localip');

	rtc.onicecandidate = function (e) {
		if (e.candidate) {
			body.innerHTML += e.candidate.candidate + '<br>';
		}
	};

metavoid

//Color utils

	function getRandomColor() {
		for (var a = "0123456789ABCDEF".split(""), b = "#", c = 0; 6 > c; c++)
			b += a[Math.floor(16 * Math.random())];
		return b
	}

	function hexToRGB(hex, alpha) {
		let r = parseInt(hex.slice(1, 3), 16),

metavoid

//Some UI and browser API helpers for different uses, part 1

//Tiny XHR

function $_$(url, cb, method, post, contenttype) {
    var requestTimeout, xhr;
    try {
        xhr = new XMLHttpRequest();
    } catch (e) {
        try {

metavoid

//Some useful JS utils, part 1
    	deepClone: function (obj) {
			return JSON.parse(JSON.stringify(obj))
		},

		uniqueArray: function(array) {
			return array.filter(function(item, pos, self) {
			    return self.indexOf(item) == pos;
			});
		},

metavoid

//Rotate array in JS
function rotateArray (array, times = 1, reverse = false){
			let arr = array.slice();
			for (let i = 0; i < times; i++) {
				if(reverse)
					arr.unshift(arr.pop())
				else
					arr.push(arr.shift())
			}
			return arr

metavoid

//Check if Object or Array is empty
function isEmpty(obj) {
	if (Array.isArray(obj) && obj.length > 0) return false;
	if (typeof obj === 'object' && Object.keys(obj).length > 0) return false;
	return true;
}

metavoid

//Recursive deep merge JS objects (unlike shallow merge of Object.assign and else)

function deepMerge(target, source) {
            let output = Object.assign({}, target);
            if (this.isObject(target) && this.isObject(source)) {
                Object.keys(source).forEach(key => {
                    if (this.isObject(source[key])) {
                        if (!(key in target))
                            Object.assign(output, {
                                [key]: source[key]

metavoid

let itemIDs = [1, 2, 3, 4, 5];

itemIDs.reduce((promise, itemID) => {
  return promise.then(_ => doSmth());
}, Promise.resolve());

metavoid

CSS Layout Debugger

A tweet-sized debugger for visualizing your CSS layouts. Outlines every DOM element on your page a random (valid) CSS hex color.

One-line version to paste in your DevTools

Use $$ if your browser aliases it:

~ 108 byte version