Re: shapes-ISSUE-27 (extensions-in-highlevel): Can extension constraints be used in the high-level language? [SHACL Spec]

Richard,

Yes, extensions should increase the vocabulary of constraints and use
the same syntactic pattern as the HL vocabulary. I don't see how that
implies that they are part of the HL vocabulary. The HL vocabulary
contains a fixed, predefined set of constraints. A HL processor would
only be expected to understand the HL vocabulary.

-- Arthur

On Thu, Apr 2, 2015 at 4:13 PM, Richard Cyganiak <richard@cyganiak.de> wrote:
> Arthur,
>
>> On 2 Apr 2015, at 20:51, Arthur Ryman <arthur.ryman@gmail.com> wrote:
>>
>> My expectation is that extensions are packaged in a seamless way so
>> you can use them without being exposed to their implementation.
>> However, that is not the same as being part of the high-level
>> language. My view is that the high-level language is a fixed set of
>> constraints defined by the WG.
>
> So you are saying that things like this should be impossible?
>
>   MyShape =
>      (propertyA maxOccurs 1)
>      OR
>      ((propertyB maxOccurs 1) AND (propertyB meets FooExtensionConstraint))
>
> I’d argue that seamless packaging of extension constraints would *require* that they can be used just like the built-in constructs of the high-level language.
>
> Best,
> Richard
>
>
>
>>
>> -- Arthur
>>
>> On Sat, Mar 28, 2015 at 4:18 PM, RDF Data Shapes Working Group Issue
>> Tracker <sysbot+tracker@w3.org> wrote:
>>> shapes-ISSUE-27 (extensions-in-highlevel): Can extension constraints be used in the high-level language? [SHACL Spec]
>>>
>>> http://www.w3.org/2014/data-shapes/track/issues/27
>>>
>>> Raised by: Richard Cyganiak
>>> On product: SHACL Spec
>>>
>>> It looks like SHACL will be split into two parts:
>>>
>>> 1) A high-level “Core/Lite” language consisting of things like cardinality constraints, datatype constraints, conjunctions and disjunctions
>>> 2) An extension mechanism that relies on embedded expressions in a more expressive language
>>>
>>> Do constraints defined using 2) become part of the high-level language, that is, can they be used in nested expressions like conjunctions and disjunctions? Or do they stand “outside” the high-level language and are directly associated with classes/individuals/etc?
>>>
>>>
>>>
>>
>

Received on Saturday, 4 April 2015 00:49:52 UTC