- From: Sandro Hawke <sandro@w3.org>
- Date: Thu, 21 Jul 2011 01:33:54 -0400
- To: Ian Davis <ian.davis@talis.com>
- Cc: RDF WG <public-rdf-wg@w3.org>
On Thu, 2011-07-21 at 01:08 +0100, Ian Davis wrote: > > I think it would be useful to talk about some of the characteristics > of these concepts e.g. equivalence > > Two TripleSets are equivalent if they conform to the bijection defined > at > http://www.w3.org/TR/2004/REC-rdf-concepts-20040210/#section-graph-equality > (i.e. they differ only in the identity of their blank nodes). > > Two TripleSet Containers are equivalent if their contained TripleSets > are equivalent > > Two TripleSet Serializations are equivalent if they parse to > equivalent TripleSets I'm not sure what this does for us; what I think is important here is identity/equality, not equivalence. 1. Two g-snaps are identical (ie the same g-snap) if they contain exactly the same triples. It hasn't occurred to me in the past, when I've said this, that b-nodes can in some theoretical sense be distinguished. Is the g-snap serialized by "<a> <b> _:c" the same as the one serialized by "<a> <b> _:d"? I guess turtle doesn't give us enough information to know. Is it the same as the one serialized by the same bytes as the first time, "<a> <b> _:c", on a second reading? Again, I guess we can't tell. Those two g-texts, read a total of three times, sure seem to me to be serializing the same one g-snap -- but maybe it's three different g-snaps which are all graph-equivalent. 2. Two g-boxes are identical (ie the same g-box) if they must by definition contain exactly the same g-snap as each other, at all points in time. 3. Two g-texts in a given syntax are identical (ie the same g-text) if they are character-by-character or byte-by-byte (depending on whether it's a character or byte syntax) the same. That is, it's just string compare. -- Sandro
Received on Thursday, 21 July 2011 05:34:03 UTC