- From: Irene Polikoff <irene@topquadrant.com>
- Date: Mon, 18 Apr 2016 15:04:27 -0700
- To: kcoyle@kcoyle.net
- Cc: "public-data-shapes-wg@w3.org" <public-data-shapes-wg@w3.org>
- Message-Id: <92C351AF-2937-4261-A985-D90FD1E91DC7@topquadrant.com>
Come to think of this some more, I don't like >> A set of shapes that defines validation rules for a data graph (?or a portion of a data graph?) is called a 'shapes graph'. It sounds like there could be a set of shapes defining validation rules and then a set of shapes defining something else. Also, not sure about using the term 'validation rules'. Any reason we can't simply say: A graph of triples representing shapes is called a 'shapes graph'. Sent from my iPhone > On Apr 18, 2016, at 2:15 PM, Irene Polikoff <irene@topquadrant.com> wrote: > > The 'groups' language only works given the context. It wouldn't work in a more general sense. One would not say that a Person groups names - this doesn't make sense, but one may say that a Family groups family members or People. > > In any case, Karen's proposed language works for me. > > Sent from my iPhone > >> On Apr 18, 2016, at 2:11 PM, Karen Coyle <kcoyle@kcoyle.net> wrote: >> >> OK, thanks, Peter. That truly wasn't clear, so I'll read further to see if this definition is followed in the text. >> >> But as an example, to me, the definition does not fit with the statement: "SHACL groups descriptive information and constraints that apply to a given data node into shapes. This document defines what it means for an RDF graph, referred to as the "data graph", to conform to a graph containing SHACL shapes, referred to as the "shapes graph"." >> >> I have trouble with "groups ... constraints ... into shapes" if a shape is an IRI/bnode. That is what made me think that shapes were intended to be graphs, not things (graphs being groups of 1 or more triples). (You wouldn't say: "groups names into Persons".) Perhaps: >> >> "A shape is an instance of the class sh:Shape, either an IRI or a blank node. The descriptive information and constraints that apply to a given data node are defined as the properties of a shape. A set of shapes that defines validation rules for a data graph (?or a portion of a data graph?) is called a 'shapes graph'. A shapes graph consists of one or more shapes." >> >> Closer? >> >> kc >> >>> On 4/18/16 9:40 AM, Peter F. Patel-Schneider wrote: >>> There may be some misunderstanding here. Shapes in SHACL are IRIs or blank >>> nodes and come from RDF graphs that are to be considered as shapes graphs. >>> RDF graphs are generally not considered to be instances of classes. >>> >>> SHACL documents should be clear that SHACL shapes are IRIs or blank nodes >>> and not graphs or sets of triples. >>> >>> >>> >>> Here is some Turtle syntax for an RDF graph >>> >>> @prefix ex: <http://example.com/> . >>> @prefix ex: <http://www.w3.org/ns/shacl#> . >>> >>> ex:s1 a sh:Shape ; >>> sh:scopeClass ex:Person ; >>> ex:property [ a sh:PropertyConstraint ; >>> ex:predicate ex:p1 ; >>> ex:valueShape ex:s2 ] ; >>> ex:constraint [ a sh:PropertyConstraint ; >>> ex:predicate ex:p2 ; >>> ex:valueShape [ a sh:Shape ; >>> ex:constraint [ a sh:NodeConstraint ; >>> sh:class ex:Student ] ] ] . >>> ex:s2 a sh:Shape ; >>> sh:constraint [ a sh:NodeConstraint ; >>> sh:nodeKind sh:IRI ] . >>> >>> When treated as a shapes graph, an RDF graph that results from this Turtle >>> syntax has three shapes in it >>> 1. http://example.com/s1 >>> 2. http://example.com/s2 >>> 3. the blank node that is allocated when matching >>> [ a sh:Shape ; >>> ex:constraint [ a sh:NodeConstraint ; >>> sh:class ex:Student ] ] >>> >>> peter >>> >>> >>>> On 04/18/2016 09:03 AM, Karen Coyle wrote: >>>> 2. Shapes >>>> >>>> Is: "Shapes are instances of the class sh:Shape and define a group of >>>> constraints that a set of focus nodes can be validated against." >>>> >>>> Suggest: "Shapes are graphs that are instances of the the class sh:Shape. >>>> Shapes define one or more focus nodes in a data graph and constraints on >>>> triples in those focus nodes. The triples in the focus nodes are validated >>>> against the constraints in the shape." >>>> >>>> I also suggest that we define "shape" as "an RDF graph of type sh:Shape" and >>>> not use "shape graph" but always use "shape" since "shape graph" is redundant. >>>> >>>> I can make this change if we have agreement on it. If I don't hear back I may >>>> make this definition an issue. >>>> >>>> kc >> >> -- >> Karen Coyle >> kcoyle@kcoyle.net http://kcoyle.net >> m: 1-510-435-8234 >> skype: kcoylenet/+1-510-984-3600 >>
Received on Monday, 18 April 2016 22:05:01 UTC