Re: TMQL: Direct (super|sub)types?

Lars,

Am 02.03.2011 um 11:04 schrieb Lars Heuer:

> Hi Rani,
> 
>> A simple use case will be just to provide a graphical visualization of
>> the hierarchies in the topic map.
> [...]
>> Or maybe, you prefer to avoid from having "direct-supertypes" and 
>> "direct-subtypes" in TMQL because we can always use association pattern
>> as an alternative:
> 
> I see. Well, I find the term "direct-" awkward. TMQL introduces a
> terminology which does not exist outside of TMQL (neither in TMDM nor
> TMRM nor (to my knowledge) in any other knowledge representation
> system) and I wonder if the mentioned use cases are common enough to
> satisfy a shortcut in TMQL. I guess my answer would be "no" and I
> wouldn't make these axes/paths first class citizens in TMQL.

I think there will be a need to distinguish between direct and all instances of a topic type. I can hardly imagine a use case case for indirect but who knows. I think the TMQL standard is the right place to establish a clear terminology for this distinction since everybody tackles this issue a little bit different. Some call it "direct" or "deep" or whatever. 

I can hardly follow the argument to omit everything that is not TMDM. The terms 'direct' and 'indirect' can be defined with just TMDM terms. It is a little bit like a propositional logic that only allows XOR (that's possible if i remember correctly :). Why not define meaningful derivates? I agree with you that they should be kept to a minimum. But i am still for a distinction between direct and all instances. I don't care about the names. Maybe there is an established terminology in graph theory which can be taken over.

Kind regards,

Robert