- From: Seaborne, Andy <andy.seaborne@hp.com>
- Date: Wed, 28 Jul 2004 10:11:21 +0100
- To: RDF Data Access Working Group <public-rdf-dawg@w3.org>
Collections: 1/ Getting the whole list Getting the whole list requires traversing an arbitrary, unknown length structure of RDF graph nodes. Fixed conjunctive/disjunctive patterns can't express this. See also (3). This is compounded by lists often being comprised of bNodes. 2/ Asking if something is contained in a list Testing whether some resource/literal is in a list is hard with fixed patterns because you need to enumerate the possibilities. 3/ Unusual structures While most RDF collections are regular rdf:first/rdf:rest/rdf:nil cons-cell structures, there is no restriction imposed for, say two rdf:first's on one slot, or multiple tails to the list, or tails that join up (well - OK - all tails join up at rdf:nil!) Containers: RDF containers are easier to deal with if there is the inference support to provide rdfs:member. But they still can have unusual structures like two rdf:_1 elements or gaps in their numbering. Andy
Received on Wednesday, 28 July 2004 05:12:09 UTC