- From: Holger Knublauch <holger@topquadrant.com>
- Date: Sun, 26 Apr 2015 12:40:33 +1000
- To: "public-data-shapes-wg@w3.org" <public-data-shapes-wg@w3.org>
On 4/26/15 11:46 AM, Karen Coyle wrote: > Holger, I agree with Jose on this. We are developing requirements. We > have not yet decided which requirements are core or not. (BTW, the > Dublin Core community is right now working on identifying its core > requirements for application profiles and validation, which we will > share with this group. It will be a small list -- less than 2 dozen > requirements.) The requirements do not "duplicate things already > solved..." etc. they are something entirely different. We had already approved a requirement https://www.w3.org/2014/data-shapes/wiki/Requirements#Expressivity:_Language_Tags If there is no distinction between core and complex requirements anyway, then why did we introduce another one? Jose confirmed that his intention was to have this in the core language, so something sounds like a contradiction to me here. If we go down this route, then we could also add duplicate requirements for all others listed under Complex constraints, such as mathematical operators. I am still unclear what we voted on. I believe we could very well add something like sh:lang, but I would not consider this "core enough" and rather put this into something like shx:lang, i.e. a library of other high-level terms that are not expected to be supported by every implementation of SHACL Core. Such an shx: library could include many other less frequently needed requirements. > > I don't understand the "once we decided that we leave the question > open whether something becomes high-level language or complex > feature..." This puzzles me because I think they are two different > things: the high-level language is how SHACL is expressed; complex > features is a categorization of types of SHACL functions. They are two > different planes and cannot be compared. There could be high level > language terms defined for complex features if we decide that those > features can be expressed in that way. Neither of these defines the core. > > We obviously need to define our own terms, since we aren't > understanding them in the same way. In my interpretation of the terminology, "High level language" is an RDF vocabulary such as sh:property, sh:minCount etc. "Core" is a high level language representing frequently needed constraints that the group finds important enough. "Complex" is the fallback mechanism, e.g. using SPARQL, to represent things that go beyond the Core, and which can be used to define new high level terms as macros. Others may have a different interpretation, and I agree it becomes difficult to discuss these things if their definitions are unclear or changing. Holger
Received on Sunday, 26 April 2015 02:41:07 UTC