this[ "set" + i ] = function(val) {
properties[i] = val;
};
This code only defines a function but doesn't execute its contents
right now, and as functions "capture" the variables defined outside of
them if you change the value of i then it will "change" in properties
[i] too. In other words the `i` in properties[i] is the same that you
use for the loop.
If you use a closure you can define a local variable that gets the
value (not the reference!) of the current index so that won't change
afterwards.
Sounds complicated but it really isn't - once you get it :)
On Dec 18, 5:52 pm, "pablo fernandez" <fernandezpabl...@gmail.com>
wrote:
> That Does it too!!
>
> I still don't get why 'i' keeps always the last value if you don't do
> var i = j; :S
>
> On Thu, Dec 18, 2008 at 1:11 PM, Balazs Endresz
>
>
>
> <balazs.endr...@gmail.com> wrote:
>
> > I've just had a look at it and where this issue comes up in the book
> > there's a new variable declared (like on page 153). No need to pass
> > the argument this way, moreover not that easy to mistype:
>
> > for ( var j in properties ) { (function(){
> > var i=j;
> > ...
>
> > I can't believe no one has spotted
> > this:http://www.apress.com/book/errata/275
>
> > On Dec 18, 4:53 pm, Pablo Fernandez <fernandezpabl...@gmail.com>
> > wrote:
> >> That did it, although I had to add this too
>
> >> -- }).call(this,i);
>
> >> in order to pass the parameter
>
> >> Thanks Balazs!!!
>
> >> On 18 dic, 12:29, Balazs Endresz <balazs.endr...@gmail.com> wrote:
>
> >> > Oops, I didn't notice it: you have to pass the `i` variable too:
> >> > for ( var i in properties ) { (function(i){
>
> >> > That's why you need the closure at all. Without that you will get the
> >> > last property from all getters.
>
> >> > The reference of `this` will always change if you put it in an
> >> > additional function, doesn't matter if it's inside an instantiated
> >> > object. Well, you can call that either design error or feature too :)
>
> >> > On Dec 18, 4:18 pm, Pablo Fernandez <fernandezpabl...@gmail.com>
> >> > wrote:
>
> >> > > another thing... why inside the anonymous function 'this' refers to
> >> > > 'window' ?? it's totally misleading...
>
> --
> Fernandez, Pablo.
