[WikiEN-l] Category intersections would be great :(

[Matt Brown]

On 6/13/06, Steve Bennett <stevagewp at gmail.com> wrote:
> I just noticed that we have [[Category:Digital cameras]] and
> [[Category:SLR cameras]], but no [[Category:Digital SLR cameras]]. How
> incredibly frustrating that the options are:

I did a lot of the setting up of these categories.  IMO, that the
category system does not support searches on intersection or
subcategory yet is not a good reason to create broken categories.

Cameras have multiple attributes, among which are brand, type and
format.  So there are, e.g.

[[Category:Canon cameras]]
[[Category:SLR cameras]]
[[Category:Digital cameras]]

There are other attributes, such as lens mount and series and the like.

The problem is: do we really want to create a category that is the
intersection of all these attributes and assume that's the only way we
want to look at them?  Or do we really want to create a category for
EACH intersection?

E.g. someone might want to look at [[Category:Canon Digital SLRs]].
But they might also want to scan [[Category:Canon EOS cameras]] or
[[Category:Canon SLRs]] or [[Category:Digital SLRs]].  Or any other
combination of attributes that we hadn't thought of.

Better, I think, to fix MediaWiki to support category intersection and
sub-inclusion in software. (perhaps this is a problem I should try and
address in code?)

-Matt