W3C home > Mailing lists > Public > public-data-shapes-wg@w3.org > May 2016

Re: New Terminology Section

From: Martynas Jusevičius <martynas@graphity.org>
Date: Wed, 11 May 2016 01:55:19 +0200
Message-ID: <CAE35Vmw4QyNbCdc8A8v7-YTBFUzLs2RzoGWe2iYVVy_h4wiZNA@mail.gmail.com>
To: Holger Knublauch <holger@topquadrant.com>
Cc: RDF Data Shapes Working Group <public-data-shapes-wg@w3.org>
Holger,

you say "inherit" in the constraint inheritance context -- before you
explained "inheritance" as instances and types. I don't think those
are the same things.

I can only give example from SPIN, not SHACL. But if I understand it
right (and I have used it quite a bit)

:subClass rdfs:subClassOf :superClass .
:superClass spin:constraint :constraint .

gives

:subClass spin:constraint :constraint .

This is very like OO, but I don't think it's what OWL cax-sco infers.
I think you need rules beyond OWL for that, like I posted.

On Wed, May 11, 2016 at 1:46 AM, Holger Knublauch
<holger@topquadrant.com> wrote:
> You mean "IF instances of superclass can have property P then instances of
> subclasses can also have property P". This aligns perfectly well with SHACL
> in that all constraints defined on superclasses "inherit" into subclasses,
> but subclasses may narrow down further. Again, we can pick another term than
> "inheritance", if that makes the spec clearer. It's all about English. I
> know why went into Computing instead...
>
> Holger
>
>
>
> On 11/05/2016 9:34, Martynas Jusevičius wrote:
>>
>> Except that in OO inheritance usually also means "IF superclass has
>> property P but subclass does not have property P THEN subclass gets
>> property P".
>>
>> Maybe the OO "inheritance" conflates several terms.
>>
>> On Wed, May 11, 2016 at 1:15 AM, Holger Knublauch
>> <holger@topquadrant.com> wrote:
>>>
>>> On 11/05/2016 4:28, Karen Coyle wrote:
>>>>
>>>> My gut feeling is that we are wavering between a standard, which can be
>>>> realized in any number of applications with varying additional
>>>> functionality, and the description of an actual application. We need to
>>>> tease those apart. (Quickly, I might add.)
>>>
>>>
>>> Would you mind elaborating this a bit more?
>>>
>>> The basic concept of OO inheritance is that "IF X is an instance of a
>>> subclass THEN X is also an instance of the superclass". This works the
>>> same
>>> way in OO as in RDFS/OWL, see
>>>
>>>      https://www.w3.org/TR/owl2-profiles/#cax-sco
>>>
>>> Whether type triples can also be inferred from the presence of certain
>>> properties is not relevant to SHACL.
>>>
>>> Holger
>>>
>>>
>
Received on Wednesday, 11 May 2016 00:03:36 UTC

This archive was generated by hypermail 2.4.0 : Friday, 17 January 2020 19:30:33 UTC