A bit of technology

I've seen a lot of articles about singletons in JS all over the web, but most of them suck, because people writing them do not know JS well enough. Even Wikipedia's examples are no good. Let's make a list of singleton "features".

1. It is usable like any other object.
2. Singleton is always the same no matter where it is called from.
3. User can not create another instance of singleton.
4. It can store some private data and have some private methods.

The simplest way to create singleton in JavaScript is to use JSON:

var Singleton = {
    data: 'Hello, world!',
    print: function() {
        alert(Singleton.data)
    }
}

Looks good and easy, right? Every object created by JSON automatically becomes singleton in JavaScript, because it does not have any constructor and can not be instantiated anywhere except for JSON statement. But this solution has one problem... Click "Read more" — a lot of text is coming your way

Read more...

Actually, you can't really blur web page in any browser except for IE6/7 - there is NO way to blur web page with CSS/JavaScript and even Canvas tag will NOT help. Too bad...

But I've found a workaround which will do the job just fine for some cases. My method adds CSS3 text-shadow property to blurred elements with the same color as text color is. Then text color "blurred" a bit to the background color. The last thing left is to find all IMG tags, replace them with Canvas, draw and blur these images inside canvas. I did not do the last step because there are plenty of code for that in Google.

Oh, and the result! Here it is (: Visit the page with Opera/Chrome/FF/Safari, click on the text, enjoy the sources!

If you are a web-developer then you definitely should know about CSS sprites. This thingie is quite old and highly used by experienced web-developers. I used this trick for the first time somewhere back in 2003-2004 when developing JavaScript game prototype for my own pleasure. No one knew the term those days, but some people already used CSS sprites in some projects, because they, like me, had a PC gaming background. And then many web-devs realized that CSS sprites do really increase application performance, so they started to write frameworks and helpful libraries to support "new" technology.

Oh, nostalgy...

Anyway, if you are not yet familiar with the topic, then do not hesitate to visit Smashing Magazine and read everything you need to know about CSS sprites!

A while ago I have written Ruby programming quickstart which includes a link to a great free book on Ruby. Now I have found another great Ruby book - Why's (Poignant) Guide to Ruby. I don't know how, but I missed it and reading it only now. I'm not a Ruby noob anymore, but this book is simply outstanding and is a must-read! It is fun, includes comic strips and, well, teaches Ruby by the way (: It is absolute joy to read this one even if you are not a programmer. C'mon! Read it yourself and give it to your kids! You definitely won't regret!

Ruby is

A dynamic, open source programming language with a focus on simplicity and productivity. It has an elegant syntax that is natural to read and easy to write.

Ruby is really cool and writting in it is a pleasure! But where to start from if you are totally new to Ruby? What to download and which IDE to use? I would recommend NetBeans. First of all it is written in Java so it is a crossplatform solution: Windows, UNIX, MacOS X are all handled. And this IDE has a lot of useful features like Ruby on Rails support, Ruby debugger and Ruby Gems installation manager. But the best feature for newcomers is bundled JRuby - a Ruby implementation in Java. So one package contains everything to get you started in no time!

You can read more about features and functionality on NetBeans Ruby page and then download it (about 60 megs).

So, everything is downloaded, what's next? I suggest reading Programming Ruby - The Pragmatic Programmer's Guide. First edition of this book is freely available online, but remember - first edition comes from year 2000 and some things are changed, so some examples will not work or will show you some kind of warning. Anyway this is the best guide to Ruby I have read, so I suggest you to buy this one (newer edition of course). Also there are tonns of documentation online available.

I hope you will enjoy programming Ruby as much as I do!