[KPhotoAlbum] Cycles in member maps

[Tero Tilus]

2007-04-04 16:02, Tuomas Suutari:
> I've been thinking to deny cycles in KPhotoAlbum's member maps.

Very good idea.

Thinking a little...  It looks like the underlying concept of these
"member maps" is set theory and "A is member of B" is to say A is a
subset of B (yes, subset, not member).

If this is (or we decide it to be ;) the case, then A is member of B,
B is member of C, and C is member A implies A equals B equals C.  It
means that essentially there are no cycles.  Therefore KPA should not
allow users to create cycles.

If we also require that A != B for any A from {tags} and B from
{tags}\A (which is to say that we do not have different names for the
same thing) we will not have cycles at all. ;)

> Can you think any (even remotely) good reason to have cycles in
> member maps

How about cities as tags and the member map relations representing
poblic transport connections?  Or companies as tags and their mutual
ownerships as relations.  I really do not know who would need
those. ;) However, you can store and represent meaningfull data that
way.

> or would anyone be happy if those weren't allowed?

Did you mean UNhappy?

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Tero Tilus ## 050 3635 235 ## http://www.tilus.net/koti/tero/