Re: [CDBI] Different subclasses for one table / Factory Pattern?

Perrin Harkins <[email protected]>
Newsgroups gmane.comp.lang.perl.modules.class-dbi
Message-ID <[email protected]>
On Thu, 2006-08-03 at 22:31 +0200, Stephan Brunner wrote:
> Right now, I'm thinking about giving up my subclasses in favour of a method 
> File->type() that tells me what kind of file I'm dealing with.

We've done that before too, and used Params::Validate to enforce the
right args to create() for each type.

>  I dislike the 
> idea because I'll have methods in package File that are invalid for certain 
> objects (for objects of wrong ->type()).

You might consider having that object delegate all the file-related
methods to another class, which it could choose based on the type.
There are some delegation/proxy modules on CPAN.  That won't work for
column accessors though.  You could verify them too, but at some point
it's just too messy.

- Perrin
lmpx.com only provides a reader for public news (NNTP) servers. It is not affiliated with the servers or forums shown here and is not responsible for the content of articles, which is written by their respective authors.