Proposal to reopen ISSUE-128 and change resolution (ISSUE-164)

Trying to close issue 164 we will have to re-open issue 128 (or issue-1)

The problem is that  the spec says SHACL engines operate on immutable
graphs but sh:defaultValueType mutates the graph prior to validation.

I propose to re-open issue 128 and re-close it by removing
sh:defaultValueType from the spec

The effect of this is that we will no longer be able to omit the rdf:type
triple from constraints
e.g.
ex:S a sh:Shape
sh:property [ *a sh:PropertyConstraint*
...
]
at least officially, SHACL engines can be lenient on this

Alternatives:
change the definition of sh:defaultValueType but this will imply to enable
more (rdfs) inference on the spec
or change the graph immutability requirement

I would be more in favor of the former solutions than the alternatives

Best,
Dimitris

-- 
Dimitris Kontokostas
Department of Computer Science, University of Leipzig & DBpedia Association
Projects: http://dbpedia.org, http://rdfunit.aksw.org,
http://aligned-project.eu
Homepage: http://aksw.org/DimitrisKontokostas
Research Group: AKSW/KILT http://aksw.org/Groups/KILT