Dusan:

“But I am simply wondering: Why are people reading this blog?”
They find it informing, and as you said, it’s well written. Perhaps you in your great experience could produce something of more interest.

“Why am I reading a blog of an 18 year old “scripter” ?”
Since when did age become of importance. I have a long time M.sc. in computer science, still I learned something reading this article. Your arrogance is your greatest flaw.

“And on top of that, all is about one poorly made scripting language … Amazing.”
You said yourself you’re using it alot. What does that make you?

Problem at line 53 character 3: Wrap the entire immediate function invocation in parens.
})(jQuery);

The code looks like:

(function($){
	$(document).ready(function(){
		// Code...
	});
})(jQuery);

Any idea what JSLint is referring to here?

one major problem with event-handling in JS is ‘this’, you never can be 100% sure what ‘this’ is

ie. you scroll or click on something and want to get the target element – some browsers give you the element by the ‘this’ keyword, others give you the page…

be careful

I just wanted to point out, so as not to confuse beginners, that a closure is not always necessray in the initial example you gave. The closure is only required if you want to access the value of “i” directly. Also, just because “i” is equal to 99 when the object is clicked, does not mean you are clicking on object 99. So if you just need to access the current object, and don’t care about outputting the value of “i”, then you can just use the this keyword instead:

var myElements = [ /* DOM Collection */ ];
 
for (var i = 0; i < 100; ++i) {
    myElements[i].onclick = function() {
        alert( 'You clicked on: ' this.id );
    };
}

So, with the above script, if you had set your elements to have incremental IDs in the HTML, then the alerted value would be equal to the ID of the object clicked. Using this can also be used to access a number of properties of the current object like this.style or this.className, etc. Only if you’re dealing with the variable value itself are you required to use a closure.

Anyhow, thanks for a nice topic of discussion.

> “This behaviour can be used in a number of different ways and has become a useful remedy for quite a few
> JavaScript gotchas; one of the most common being the “looping problem”.

the Javascript gotcha you mention happens the onclick anonymous function closes over a binding to a mutable variable, it is non intuitive but not incorrect! Intuitively, one expects a new binding to a fresh variable at every iteration, that’s what would happen in a language where immutability is the default.

See http://math.andrej.com/2009/04/09/pythons-lambda-is-broken/
and http://lambda-the-ultimate.org/node/2648

> I also do use (a lot) javascript and after 15+ years of “real” languages porffesional usage, I came to a
> conclusion that javascript has its appeal *only* inside HTML. It allows for very quick development of
> “awesome stuff”, although not always relevant. And of course browser made this combination realy
> ubiquitous.

Seriously, don’t people ever tire of that “real professional languages” rant ?
Javascript is a cool mix of Scheme and Self (two languages way cooler than most “real” languages.
Javascript is the web lingua franca.
Javascript implementation have upped their games tremendously in the past year, V8 is faster than PHP, CPython, MRI, etc…
Javscript is indeed making inroads outside the browser (http://en.wikipedia.org/wiki/Server-side_JavaScript), coding your whole web app in one language does makes sense, goodbye impedance mismatch

@Dusan why are you reading this blog if you think it’s pointless?

your blog is great, keep up the good work.

I’m using closures for iteration (simplified example):

var myarr = ["a", "b", "c"];
 
function iterator(arr) {
	var idx = 0;
	return function () {
		return arr[idx++];
	}
}
 
var getNext = iterator(myarr);
 
getNext(); // a
getNext(); // b
getNext(); // c

Best Regards,

Björn