"Is a Property a Class" and other DAML questions

Just a few items that have been bothering me:

1) Is a Property a Class?
	Can you put Properties in the places where Classes are allowed?
	(ex. PropA sameClassAs PropB)
2) Can something be both a Property and a Class?
	is daml:TransitiveProperty both a Property and a Class?

In some places such as http://www.daml.org/2000/12/daml+oil.daml
the answers to the above seem to be "yes", however
in others such as 3.1.3 of
http://www.daml.org/2000/12/axiomatic-semantics.html,
which says that "properties and classes are disjoint",
the answers seem to be "no"


3) What is the relationship between an Ontology and a Namespace?

Are you allowed to define 2 Ontologies in the same Namespace? If so,
then when triples are created, how do you know which things belong to
which Ontology?
I guess my confusion here is what exactly does daml:Ontology do and how
does it bring together all the other stuff lying around the same document?


4) more of a comment than a question...
For Restrictions, can I do the following? (I assume yes)
-----------------------
<daml:NonNegativeInteger rdf:ID="1"/>

<daml:Restriction rdf:ID="CarRestrictions">
  <daml:cardinality rdf:resource="#1"/>
  <daml:onProperty rdf:resource="#hasEngine"/>
</daml:Restriction>

<daml:Class rdf:about="#Car">
  <rdfs:subClassOf rdf:resource="#CarRestrictions"/>
</daml:Class>

<daml:Class rdf:about="#Truck">
  <rdfs:subClassOf rdf:resource="#CarRestrictions"/>
</daml:Class>
----------------------

Now given the above can I add the following? (I assume no)
----------------------
<daml:NonNegativeInteger rdf:ID="2"/>

<daml:Restriction rdf:about="CarRestrictions">
  <daml:mincardinality rdf:resource="#2"/>
  <daml:onProperty rdf:resource="#hasDoors"/>
</daml:Restriction>
---------------------

At this level this 'seems' good, however when triples are created
all the stuff in CarRestrictions gets mashed together.
I was putting together an example of bad DAML for fun and this
one came very naturally. I can see bugs like this being common 
as more DAML is created by more people.



thanks,
Corey

Received on Monday, 5 March 2001 11:48:53 UTC