Re: TMQL: Direct (super|sub)types?
Benjamin Bock <[email protected]>
| Newsgroups | gmane.text.xml.xtm.general |
|---|---|
| Message-ID | <[email protected]> |
On Sat, Mar 5, 2011 at 12:46 AM, Lars Heuer <[email protected]> wrote: > [...] >>> You can fall back to assocs: >>> >>> t1 / tmdm:supertype-subtype(tmdm:subtype -> tmdm:supertype) >>> >>> t1 / tmdm:type-instance(tmdm:instance -> tmdm:type) > >> Except if you decide to have those filtered out in the environment. > > I don't understand your argument. Why shouldn't the above mentioned > path expressions work (ignoring the fact that TMQL engines would > optimize these kind of path expressions)? Some engines treat type-instance as associations, some don't. Some treat supertype-subtype as associations, some don't. In Topic Maps APIs (e.g. TMAPI, MaJorToM-API), some users (including me) choose to hide those special associations while they are managed "directly", i.e. as properties instead of associations. Doing the same in TMQL may save a bit of filtering. That's why it may be useful to have the option to switch their association-representation off. In this case, I'd still be able to query the non-transitive version. Cheers, Benjamin _______________________________________________ topicmapmail mailing list [email protected] http://www.infoloom.com/mailman/listinfo/topicmapmail