Perl Mongers Meeting Next Wednesday - dans waffling

[Dan Morrison]

> Grant McLean writes:
> >Ewen had offered to talk on state machines/code generation, or
> >parsing SGML/XML.  (Is that offer still open Ewen?)
>
> Providing I know which of those topics people are more interested in,

Parsing XML is dull, (with the odd bit of stress thrown in by character
entities).
Validating it is more challenging.
Actually _USING_ XML would be interesting.
I've been doing serious XSL stuff with XML::XSLT (My stylesheet is a Turing
machine!) and would like to see what anyone else has actually achieved.

I'm unsure what 'state machines/code generation' would entail, therefore it
my be even more instructive to me. I have visions in my head of 'life' and
'core wars'. Am I on the right track? If so these topics would cover the two
extreme ends of the 'Information Age', timeline-wise ;-)

I've failed to turn up the last two times, but I'll try harder if there's
some XML to be seen.


And as for group therapy - my question is:
When is it correct to subclass an object and end up with all its baggage,
and when is it better to create a new object that contains little more than
a handle and accessors to an instance of your desired object? In the second
case, what are the gotchas with AUTOLOAD?

Case in point : I've subclassed XML::Document into XML::Sitemap(my own pm),
as I like being able to manipulate the heirachical structure directly, yet
I've added functions like 'spider', 'summarize-site' and serialization and
rendering to it. I feel there's something inelegant about this, but I don't
know what.
I thought it was using inheiritance efficiently, but it seems to be muddying
the waters (Not least because I've now come across modules that check (ref
$obj eq "XML::Document") and not (obj->isa("XML::Document")) Arrg.  )

... sorry, I guess I should write this on a bit of paper next week, but now
I finally figured out what my burning Perl issue of the day was, I had to
share.


.dan.