Greg Lavallee elgreg

Learn JavaScript concepts with the Chrome DevTools

Authored by Peter Rybin , Chrome DevTools team

In this short guide we'll review some new Chrome DevTools features for "function scope" and "internal properties" by exploring some base JavaScript language concepts.

Closures

Let's start with closures – one of the most famous things in JS. A closure is a function, that uses variables from outside. See an example:

Quick virtualenv fix on Mountain Lion

Overview

It appears that Apple somehow broke Python in Mountain Lion, so even with the latest Command Line Tools and Xcode 4.4 virtualenv won't properly work. During virtual environment creation it will try to install easy_install inside /Library hierarchy. So let's give it a quick workaround. Let's install custom python into your $HOME-directory using pythonbrew!

Installing proper Command Line Tools

Without the Apple Mac Developer account you won't even see the proper download link for the latest CL Tools and the old one won't work on ML. So here's the link: http://goo.gl/iBTXh. It points towards the Apple website so don't worry.

this sucks, but it works. centos should really just build the damn ca-certificates package for centos5 found on centos6

cp /etc/pki/tls/certs/ca-bundle.crt /root/ca-bundle.crt-old
curl http://curl.haxx.se/ca/cacert.pem -o /etc/pki/tls/certs/ca-bundle.crt

#Four Ways To Do Pub/Sub With jQuery and jQuery UI (in the future)

Between jQuery 1.7 and some of work going into future versions of jQuery UI, there are a ton of hot new ways for you to get your publish/subscribe on. Here are just four of them, three of which are new.

(PS: If you're unfamiliar with pub/sub, read the guide to it that Julian Aubourg and I wrote here http://msdn.microsoft.com/en-us/scriptjunkie/hh201955.aspx)

##Option 1: Using jQuery 1.7's $.Callbacks() feature:

$.Callbacks are a multi-purpose callbacks list object which can be used as a base layer to build new functionality including simple publish/subscribe systems. We haven't yet released the API documentation for this feature just yet, but for more information on it (including lots of examples), see my post on $.Callbacks() here:

	class Foo
	@_cattr =
	"a": "apple"
	"b": "banana"
	"c": "cherry"
	"d": "dragonfruit"

	@classCattrGet: ->
	@_cattr

	var asyncApi = asyncApi \|\| (function(win) {

	var asyncApi = function(globalName, queueName, createGlobal) {

	var global = win[globalName];
	if(!global && createGlobal) {
	global = win[globalName] = {};
	}
	if(global) {
	var queue = global[queueName] \|\| [];

	// modified John Resig's http://ejohn.org/projects/flexible-javascript-events/

	var div = document.createElement('div');

	var addEvent, removeEvent;

	if ( div.addEventListener ) {
	addEvent = function( elem, type, fn ) {
	elem.addEventListener( type, fn, false );
	};

	<h1>
	Stop the App Store upgrade prompt</h1>
	<p>
	Fortunately I saved my copy of Skitch (version 1.0.12) after hearing <a href="http://twitter.com/danielpunkass">Daniel Jalkut</a> (developer at <a href="http://www.red-sweater.com/">Red Sweater Software</a> best known for <a href="http://www.red-sweater.com/marsedit/">MarsEdit</a> and <a href="http://www.red-sweater.com/fastscripts/">FastScripts</a>) mention that a brief stint with Skitch 2.0 had sent him back to Skitch version 1.</p>
	<p>
	The only problem is that the Mac App Store app kept telling me that Skitch needs to be updated. I even went into my Purchases list and '"hid" Skitch, but still the App Store kept telling me that it wanted to update Skitch.</p>
	<p>
	I seem to have found a solution, which was to quit Skitch.app, and then locate the app in /Applications/ using the Finder. Once there, I control-clicked on the app and chose "Show Package Contents":</p>
	<p style="text-align:center">
	<img alt="" border="0" height="143" src="htt

	//addEventListener polyfill 1.0 / Eirik Backer / MIT Licence
	(function(win, doc){
	if(win.addEventListener)return; //No need to polyfill

	function docHijack(p){var old = doc[p];doc[p] = function(v){return addListen(old(v))}}
	function addEvent(on, fn, self){
	return (self = this).attachEvent('on' + on, function(e){
	var e = e \|\| win.event;
	e.preventDefault = e.preventDefault \|\| function(){e.returnValue = false}
	e.stopPropagation = e.stopPropagation \|\| function(){e.cancelBubble = true}

	from selenium.common.exceptions import NoSuchElementException, TimeoutException


	class DomHelper(object):
	driver = None
	waiter = None

	def open_page(self, url):
	self.driver.get(url)