staltz

The introduction to Reactive Programming you've been missing

(by @andrestaltz)

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This tutorial as a series of videos

If you prefer to watch video tutorials with live-coding, then check out this series I recorded with the same contents as in this article: Egghead.io - Introduction to Reactive Programming.

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DiegoSalazar

// Takes a credit card string value and returns true on valid number
function valid_credit_card(value) {
  // Accept only digits, dashes or spaces
	if (/[^0-9-\s]+/.test(value)) return false;

	// The Luhn Algorithm. It's so pretty.
	let nCheck = 0, bEven = false;
	value = value.replace(/\D/g, "");

	for (var n = value.length - 1; n >= 0; n--) {

bobbygrace

Hello, visitors! If you want an updated version of this styleguide in repo form with tons of real-life examples… check out Trellisheets! https://github.com/trello/trellisheets

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Trello CSS Guide

“I perfectly understand our CSS. I never have any issues with cascading rules. I never have to use !important or inline styles. Even though somebody else wrote this bit of CSS, I know exactly how it works and how to extend it. Fixes are easy! I have a hard time breaking our CSS. I know exactly where to put new CSS. We use all of our CSS and it’s pretty small overall. When I delete a template, I know the exact corresponding CSS file and I can delete it all at once. Nothing gets left behind.”

You often hear updog saying stuff like this. Who’s updog? Not much, who is up with you?

paulirish

Screencapture and animated gifs

I say "animated gif" but in reality I think it's irresponsible to be serving "real" GIF files to people now. You should be serving gfy's, gifv's, webm, mp4s, whatever. They're a fraction of the filesize making it easier for you to deliver high fidelity, full color animation very quickly, especially on bad mobile connections. (But I suppose if you're just doing this for small audiences (like bug reporting), then LICEcap is a good solution).

Capturing (Easy)

1. Launch quicktime player
2. do Screen recording

v-yarotsky

### INSTALLATION NOTES ###
# 1. Install Homebrew (https://github.com/mxcl/homebrew)
# 2. brew install zsh
# 3. Install OhMyZsh (https://github.com/robbyrussell/oh-my-zsh)
# 4. brew install reattach-to-user-namespace --wrap-pbcopy-pbpaste && brew link reattach-to-user-namespace
# 5. Install iTerm2
# 6. In iTerm2 preferences for your profile set:
#      Character Encoding: Unicode (UTF-8)
#      Report Terminal Type: xterm-256color
# 7. Put itunesartist and itunestrack into PATH

wesbos

// 🔥 Node 7.6 has async/await! Here is a quick run down on how async/await works

const axios = require('axios'); // promised based requests - like fetch()

function getCoffee() {
  return new Promise(resolve => {
    setTimeout(() => resolve('☕'), 2000); // it takes 2 seconds to make coffee
  });
}

DmitrySoshnikov

@kangax's ES6 quiz, explained

@kangax created a new interesting quiz, this time devoted to ES6 (aka ES2015). I found this quiz very interesting and quite hard (made myself 3 mistakes on first pass).

Here we go with the explanations:

Question 1:

(function(x, f = () => x) {

hdragomir

<script type="text/javascript">
    (function () {
      "use strict";
      // once cached, the css file is stored on the client forever unless
      // the URL below is changed. Any change will invalidate the cache
      var css_href = './index_files/web-fonts.css';
      // a simple event handler wrapper
      function on(el, ev, callback) {
        if (el.addEventListener) {
          el.addEventListener(ev, callback, false);

necolas

/*
 * Updated to use the function-based method described in http://www.phpied.com/social-button-bffs/
 * Better handling of scripts without supplied ids.
 *
 * N.B. Be sure to include Google Analytics's _gaq and Facebook's fbAsyncInit prior to this function.
 */

(function(doc, script) {
    var js, 
        fjs = doc.getElementsByTagName(script)[0],

pies

/* Based on 
 * - EGM Mathematical Finance class by Enrique Garcia M. <egarcia@egm.co>
 * - A Guide to the PMT, FV, IPMT and PPMT Functions by Kevin (aka MWVisa1)
 */

var ExcelFormulas = {

	PVIF: function(rate, nper) {
		return Math.pow(1 + rate, nper);
	},