ivoa-std/DALI

vocabulary for "xtype" ?

Opened this issue · 1 comments

Hi all,

I see that there are many addition of xtype values in the DALI issues.

What if we move the list of xtype values into an IVOA vocabulary, which would be managed jointly between DAL and Semantics?

Cheers,
Baptiste

xtypes come along with specification of how to serialise values, possibly valid ranges, and stuff like that... it seems like maybe a stretch for a vocabulary which really concentrates on semantic definition. I do agree that the process of maintaining a set of xtypes would be simpler.

However, the number of xtypes in the doc and in issues right now is actually just representative of all the ones I have come to need (this was in response to a question about how many possible xtypes would DALI ever need). I don't see the list growing much beyond this because anything more complex strays into being a data model rather then a type. And actually, I only think that range, uri, and uuid are directly useful; phrases and words are there to provoke discusssion about VOTable vs DALI/xtype being the place to support these concepts and we may decide against the xtype solution.