Subj : Re: Hook into Array
To   : netscape.public.mozilla.jseng
From : Sterling Bates
Date : Wed Apr 21 2004 10:57 am


"Niklas Lindquist" <niklaslindquist@hotmail.com> wrote in message
news:c65q9n$nrm1@ripley.netscape.com...
> Is there a way to hook into predefined classes e.g. the Array class to get
> notifications when individual objects are inserted/reassigned/deleted, or
> when the entire Array is sorted or reversed?

No -- you have to create your own Array implementation.  It's pretty easy,
though.

> Also, is there a way to not initialize array elements until its values are
> requested?

In your custom Array class, use the getProperty hook to return the values on
the fly.  Use JSVAL_TO_INT on the id parameter and you'll have the index
value requested by the script (check JSVAL_IS_INT(id) first, though <g>).

> By the way, are there any constraints regarding the number of elements to
> the Array class, except runtime memory?

That depends on whether there's an overall property limit -- I don't think
there is (except memory as you say).

Sterling

.