- From: Simon Spero <sesuncedu@gmail.com>
- Date: Sun, 6 Jul 2014 16:05:51 -0400
- To: Tim Berners-Lee <timbl@w3.org>
- Cc: semantic-web@w3.org, Victor Porton <porton@narod.ru>, Paul Tyson <phtyson@sbcglobal.net>
- Message-ID: <CADE8KM5UnYpN=hRYPG8h1VXVPwaqjw=D=sge-3X9ZRgR7UMJ8w@mail.gmail.com>
[I'm not sure if the original poster is looking to construct trees of rdf statements, represent trees in rdf, or represent n-ary predicates. The last requires creating a new object. Some patterns for doing this are described in [2] (this note predates OWL 2.0, so HasKey axioms were not available).] On Jul 6, 2014 12:20 PM, "Tim Berners-Lee" <timbl@w3.org> wrote: > Any serializer to turtle, etc, produces a tree in the process. Asterisk: a good turtle serializer will tree things up as much as possible (streaming processors may have time/memory constraints). A bad serializer is free to output one triple at a time (technically a tree :) . An evil serializer is free to output a few gigatrips in the n-triples subset, then throw in a [] (a non-evil n-quads serializer may emit a few gigatrips, reach the end of the default graph and stop being turtle or Trig). This is a pain if you're trying to write code to guess serialization formats without processing the entire document... > In general, a graph may have disconnected parts and so may have to be serialized to more than one tree. Obelisk: If RDF interpretation is allowed, there's always a pseudo root of rdf:Property available without too much cheating [1]. > (Note that if you allow N3's reverse arc syntax ( <#a> is :child of <#b> ) the you can serialize any acyclic graph to turtle without having to generate arbitrary identifiers for blank nodes, just using the turtle [ ] syntax. That is one reason why it was a shame that the reverse syntax was omitted from Turtle.) I'd rather have n3 @forSome, add named, linkable [], and made the prefix for blank nodes be "_I_cannot_think_of_any_reasonable_name_for_this_entity_" followed by 80 emoji of a sad kitten 😿 , because blank nodes should get syntactic sour 😉 . Simon [1] http://www.w3.org/TR/2014/REC-rdf11-mt-20140225/#rdf-interpretations [2] http://www.w3.org/TR/swbp-n-aryRelations
Received on Sunday, 6 July 2014 20:06:22 UTC