[XML-DEV Mailing List Archive Home] [By Thread] [By Date] [Recent Entries] [Reply To This Message] Re: RE: Abstraction in Science, Mathematics, Software, and Mar
typo correction: > Maybe it could be logically defined (according to > Roger's 'crossProduct' proposal) crossProductThing to which every > can have an 'is-a' relationship. I meant: Maybe it could be logically defined (according to Roger's 'crossProduct' proposal) crossProductThing to which every thing in a schema represented by an element (and/or type?) can have an 'is-a' relationship. ---- Stephen D Green On 14 March 2011 14:04, Stephen D Green <stephengreenubl@gmail.com> wrote: > Maybe there is an (extended) XSD meta-meta-type akin to the OWL > 'Thing' which is completely abstract with every possible 'has-a' and > every possible 'is-a'. Maybe it could be logically defined (according to > Roger's 'crossProduct' proposal) crossProductThing to which every > can have an 'is-a' relationship. In UBL we had a concept in the early > days of what we called an 'Ur-type' (after the city Ur from which > supposedly every language developed?). That seems to be similar. > > These levels of abstraction do seem to have parallels in the ISO CCTS > implemented by languages such as UBL which then provides the data > dictionary naming conventions. > > ---- > Stephen D Green > > > > On 12 March 2011 23:14, Michael Kay <mike@saxonica.com> wrote: >> On 12/03/2011 10:34, Costello, Roger L. wrote: >>> >>> Hi Stephen, >>> >>>> Are you suggesting or even hinting that it should be possible >>>> to define a type whose contents are types rather than elements? >>> >>> Funny you should ask! Yes! >>> >>> A couple weeks ago I pitched that very idea on the xmlschema-dev list: >>> >> >> Well, "complexType" and "simpleType" are the names of two types whose >> instances are types - the set of complexTypes and the set of simpleTypes >> respectively. I guess Roger's "cross-product" is another type whose >> instances are types, though he presented it more as a constructor for new >> types, akin to construction-by-list and construction-by-union. >> >> The IRDS model from the 1980s had four layers: loosely, objects like "John >> Smith", types like "Person", meta-types like "Complex Type", and >> meta-meta-types like "Concept". The things in each layer are instances of >> the types in the layer above. The idea was that the meta-meta-types were >> fixed (they define the ontological framework), but the meta-types are >> completely extensible - the idea being that you can always incorporate new >> "data models" like the relational model, the XML model, etc. >> >> I put "data model" in quotes, because one of the problems is that the term >> is used by some people to mean a set of types like "Person", and by others >> to mean a set of meta-types like "Complex Type". >> >> Michael Kay >> Saxonica >> >> _______________________________________________________________________ >> >> XML-DEV is a publicly archived, unmoderated list hosted by OASIS >> to support XML implementation and development. To minimize >> spam in the archives, you must subscribe before posting. >> >> [Un]Subscribe/change address: http://www.oasis-open.org/mlmanage/ >> Or unsubscribe: xml-dev-unsubscribe@lists.xml.org >> subscribe: xml-dev-subscribe@lists.xml.org >> List archive: http://lists.xml.org/archives/xml-dev/ >> List Guidelines: http://www.oasis-open.org/maillists/guidelines.php >> >> >
[Date Prev] | [Thread Prev] | [Thread Next] | [Date Next] -- [Date Index] | [Thread Index] |
PURCHASE STYLUS STUDIO ONLINE TODAY!Purchasing Stylus Studio from our online shop is Easy, Secure and Value Priced! Download The World's Best XML IDE!Accelerate XML development with our award-winning XML IDE - Download a free trial today! Subscribe in XML format
|