Thanks for the quick reply. I understood about closures and keeping
things private, but got sort of confused where I saw usage of:
(function(){
var hello = this.hello = 'yo';
and nowhere hello was used down in the code. But I think it could be
there just as a standard anyway so I you would edit the code you don't
have to think about it and you could just use 'hello' somewhere as you
already defined it.
})()
about the ;function or !function etc. thanks for clearing up that
chars like + or ~ would also 'work' -- again, I understood from
reading elsewhere that people suggested the compressor would be wrong
and should be looked at if the extra ! or ; before the parenthese was
necessary to prevent errors (since trailing semi colons are not
required). But still I would see it being used inside files which made
me frown my eyebrows again.
On May 15, 8:36 pm, Arian Stolwijk <[email protected]> wrote:
> You should read about closures.
>
> They help to prevent putting all kind of variables public.
>
> so you can wrap it with in a closure, or self-invoking-function, there are
> several names and methods, but the basic example used in MooTools is:
>
> (function(){
>
> var private = 'yo';
>
> })();
>
> alert(private); // throws error
>
> But we don't want to put everything privately, but want to make it
> public. Fortunately we can just put something on the window object. The
> window object is equal to `this` in the browser:
>
> console.log(window == this);
>
> This is also true in closures:
>
> (function(){
>
> this.hello = 'yo';
>
> })();
>
> console.log(window.hello, this.hello, hello); // yo
>
> For better compression you can do something like this:
>
> (function(){
>
> var hello = this.hello = 'yo';
>
> // now we can use hello here, which is private, instead of this.hello every
> thime
>
> })();
>
> In 1.3.1 and in PowerTools .call(this) was used. .call and .apply work like
> bind, but also execute the function. So here the inner this was set to the
> outer this, which was still window. This supposed to fix something in some
> fancy environments, but didn't work in node.js after all, since this refers
> to something else there and not the global object.
>
> There are also other variants to fix nasty errors with compressing, when the
> last ; is forgotten, see this example, which works ok
>
> (function(){
>
> })()
> (function(){
> })()
>
> but when we compress:
>
> (function(){})()(function(){})()
>
> which errors.
>
> Putting some other char before the (function(){, like a !, ; ~, + or
> whatever solves this problem.
>
> I hope this helps you and I've given you some pointers to search further.
>
>
>
> On Sun, May 15, 2011 at 8:16 PM, Rolf -nl <[email protected]> wrote:
> > Looking at Moo's source and following the syntax and code style rules
> > I was (in the past) used to do it like:
>
> > var myClass = new Class({
> > });
>
> > then people started to wrap it and adopted:
>
> > (function(){
>
> > var myClass = new Class({
> > });
>
> > })();
>
> > or an alternate ending for the wrap (like in cpojer's powertools):
>
> > }).call(this);
>
> > ryan florence is dropping trailing semi-colons in his (non mootools
> > released) js code (which is fine I think, others can disagree) but
> > starting code with a semi-colon before every parenthese like:
>
> > ;(function(){
> > })();
>
> > and I also noticed this:
>
> > var myClass = this.myClass = new Class({
> > });
>
> > since when are we also adding this.myClass? What is the benefit, why
> > is it important?
>
> > Ok, what I'm trying to say is that I see sort of the use of all of
> > this and I understand what it does, but I don't fully 'get' the path
> > to follow or why I would do it one way or the other.
>
> > Maybe someone can enlighten us here on the list or maybe a blog post
> > to take away some confusion.
