MooTools team suprised us by releasing 1.3 beta. One of the most notable features was Slick – very fast selector engine. It does not use MooTools code, so finally we can use it without attaching whole MooTools Core. On other side, as everybody knows, jQuery seems to have fastest selector engine among JavaScript libraries – SizzleJS . So include SizzleJS or Slick? Check our benchmarks and decide yourself.

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I’ve described tools like QUnit or JSSpec. They allow us to test JavaScript functions, classes, generally things that works without refreshing the page. But what if we need to check existance of “Log in” page, whether navigation works properly or user is able to modify settings of his account. These actions require loading several pages on different browsers and systems. Here comes Selenium. Suite of tools to automate web app testing across many platforms.

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This post is inspired by Brian Leroux and his wtfjs tumblr blog. JavaScript is full of unexplained oddities. I’m going to prove you that every each of them can be explained. There are several causes of such interpreter behavior: inaccurate specification, hyper-correct interpreting, understatements, waywardness of browsers creators. The first type of such ‘features’ are these related to comparing.

0.1 + 0.2 == 0.3

11111111111111113 != 11111111111111111

01234 != 0668

0123 == "0123"

NaN == NaN

3 != "03"

"4" - "1" == "1" + "2"

If you think that TRUE is answer to any of above expressions (and don’t know why it’s exactly opposite) then you should certainly read rest of this article.

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JavaScript is not only for webpages and web applications. Among other things, You can create realtime applications, serverside solutions, desktop and mobile applications. There are two types of moble applications: running in browser and native ones. These latter are often faster and more powerful. That’s because they have access to filesystem, accelometer, camera and et ceatera. Native applications are usually written in phone-specific language like Objective-C or Java, hence stanalone programmers generally choose HTML+CSS+JavaScript solutions. Happily, thanks to lastest technology, we are able to easily transform browser application into truly native one.

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