Re: Shapes, Individuals, and Classes - OSLC Motivations

Eric,

Yes. RDF includes the built-in XML datatypes.
_________________________________________________________
Arthur Ryman
Chief Data Officer
SWG | Rational
905.413.3077 (phone) | 416.939.5063 (cell)
IBM InterConnect 2015




From:   "Eric Prud'hommeaux" <eric@w3.org>
To:     "Peter F. Patel-Schneider" <pfpschneider@gmail.com>, 
Cc:     Arthur Ryman/Toronto/IBM@IBMCA, public-data-shapes-wg@w3.org
Date:   11/07/2014 08:46 AM
Subject:        Re: Shapes, Individuals, and Classes - OSLC Motivations



* Peter F. Patel-Schneider <pfpschneider@gmail.com> [2014-11-06 
20:36-0800]
> So your view is that all that counts is the graph?  Nothing about
> datatypes, or RDF, or RDFS?

I suspect that OSLC wants datatypes, noting that Resource Shapes has
an oslc:valueType predicate for identifying the datatype of a literal.

  http://www.w3.org/Submission/2014/SUBM-shapes-20140211/#valueType


> peter
> 
> 
> On 11/06/2014 12:01 PM, Arthur Ryman wrote:
> >Peter,
> >
> >Commenting on your proposed wording of how to express the "decoupling"
> >requirement. I'd go further and demote the notion of class to being 
more
> >like just another property and view the shape/constraints as applying 
to
> >the RDF representation of an information resource, i.e. to a set of
> >triples (aka an RDF graph). Some of the triples will have rdf:type as 
the
> >predicate and those triples are useful for locating certain subject 
nodes
> >that we want to say more things about, e.g that they are the subjects 
of
> >triples that have certain other predicates, etc.
> >_________________________________________________________
> >Arthur Ryman
> >Chief Data Officer
> >SWG | Rational
> >905.413.3077 (phone) | 416.939.5063 (cell)
> >IBM InterConnect 2015
> >
> >
> >
> >
> >From:   "Peter F. Patel-Schneider" <pfpschneider@gmail.com>
> >To:     Arthur Ryman/Toronto/IBM@IBMCA,
> >Cc:     public-data-shapes-wg@w3.org
> >Date:   11/06/2014 12:14 PM
> >Subject:        Re: Shapes, Individuals, and Classes - OSLC Motivations
> >
> >
> >
> >I still don't know what "custom" means here with respect to RDF.  As 
far
> >as I
> >can tell any bit of an ontology, or class, or property, or constraint, 
or
> >shape could be called "custom".  Now it may be that within OSLC there 
is
> >some
> >notion of custom vs non-custom, but how can that notion be removed from
> >OSLC
> >so that it can be used elsewhere?
> >
> >Similarly, the notions of "specification", "implementation", "project",
> >etc.,
> >appear to me to be specific to OSLC, and particular to the design
> >methodology
> >you outline below, and using them to drive a spec could, I think, tie 
that
> >
> >spec quite closely to the design methodology.
> >
> >
> >
> >As a contrast, here is what I believe should be used to say that 
classes
> >and
> >shapes/constraints are decoupled.
> >
> >Definition:  Classes and shapes/constraints are decoupled if the
> >specification
> >can use different sets of shapes/constraints on the same class.  For
> >example,
> >if the specification permits the ontology
> >    ex:Person rdf:type rdfs:Class .
> >    ex:name rdf:type rdf:Property .
> >    ex:name rdfs:domain ex:Person .
> >to be used with the constraint set
> >    ex:Person < exists ex:name
> >(every person has a "known" value for its name)
> >or used with the constraint set
> >    ex:Person < all ex:name xsd:string
> >(all "known" names of people are strings)
> >then it will be said to allow the decoupling of constraints/shapes and
> >classes.
> >
> >
> >A stronger notion would be that shapes/constraints are independent of
> >classes.
> >   This could be defined as:
> >
> >Definition:  Classes and shapes/constraints are independent if some
> >shapes/constraints do not use class membership in their definition. For
> >example, the following constraint is class-independent:
> >    exists ex:name < exactly 1 ex:name
> >(if something has a "known" name then it has exactly one "known" name)
> >
> >
> >peter
> >
> >
> >
> >
> >On 11/06/2014 04:59 AM, Arthur Ryman wrote:
> >>Peter,
> >>
> >>OSLC defines specification for RDF representation of resources in
> >several
> >>domains, e.g. Requirements, Quality, Change Management etc. A
> >>specification typically defines a class and several properties.
> >>Implementations are allowed to add new RDF properties but they don't
> >>necessarily introduce new RDF classes. Furthermore, within an
> >>implementation, users may add custom RDF properties on a
> >>project-by-project basis, but that doesn't change the RDF class.
> >Therefore
> >>different projects use different Shapes but the Shapes only differ by
> >RDF
> >>properties, not RDF classes. That is what I mean by decoupling Shapes
> >and
> >>Classes.
> >>
> >>I will elaborate this on the wiki.
> >>_________________________________________________________
> >>Arthur Ryman
> >>Chief Data Officer
> >>SWG | Rational
> >>905.413.3077 (phone) | 416.939.5063 (cell)
> >>IBM InterConnect 2015
> >>
> >>
> >>
> >>
> >>From:   "Peter F. Patel-Schneider" <pfpschneider@gmail.com>
> >>To:     Arthur Ryman/Toronto/IBM@IBMCA, public-data-shapes-wg@w3.org,
> >>Date:   11/05/2014 05:27 PM
> >>Subject:        Re: Shapes, Individuals, and Classes - OSLC 
Motivations
> >>
> >>
> >>
> >>I'm still wondering what you think it means to decouple shapes and
> >>classes.
> >>The first motivation you provide is supported by both SPIN and OWL
> >>constraints.  I can't figure out what custom properties have to do 
with
> >>classes, or constraints, or shapes.  The behaviour you appear to be
> >>looking
> >>for in your second paragraph is also supported by both SPIN and OWL
> >>constraints.
> >>
> >>I had thought that this was ironed out at the Face-to-Face, but I 
guess
> >>not.
> >>
> >>peter
> >>
> >>
> >>On 11/05/2014 01:47 PM, Arthur Ryman wrote:
> >>>There are a few motivations for decoupling shapes and classes. One is
> >>that
> >>>the creation shape may be different than the update shape. Another 
has
> >>to
> >>>do with custom properties. I'll write up the following in the wiki.
> >>>
> >>>OSLC supports an open content model for resources. It is common for
> >>tools
> >>>to add their own custom properties, and for projects within a tool to
> >>have
> >>>different user-defined properties. For example, consider a bug 
tracking
> >>>tool. Project A may add a custom property foo and project B may add
> >bar.
> >>>All projects use the same RDF type for bug resources, e.g.
> >>>oslc_cm:ChangeRequest. However, the shape for resources in project A
> >>>differs for the shape for project B.
> >>>_________________________________________________________
> >>>Arthur Ryman
> >>>Chief Data Officer
> >>>SWG | Rational
> >>>905.413.3077 (phone) | 416.939.5063 (cell)
> >>>IBM InterConnect 2015
> >>>
> >>>
> >>
> >>
> >>
> >
> >
> >
> 

-- 
-ericP

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Received on Monday, 10 November 2014 15:39:26 UTC