N3 changes from Tim Berners-Lee on 2001-05-21 (www-rdf-interest@w3.org from May 2001) (original) (raw)

An unusually large number of changes having happened to N3 recently, I list them for any N3 followers

• There is now a distinction between a document (a doc:Work) and the N3 formula it parses to. This is important whwn one actually starts to look at the loading and parsing of documents; it is also plogically essential as forumlae have an identity which is strictly their content whereas many documents may have different characteristicsn but parse to the same thing in N3 or XML.

The main effect of this is that where one has said "<> log:forAll :x, :y, :z" one must use the keywpord "this" instead of "<>" to refer to the current context instead of the current document. The parsers currently generate an id "#_formula" for the context but one must NOT rely on that.

The RDF/XML equiva;lent of "this" I haven't come up with yet. @@

• Some namespaces have changed. The biggest change is the removal of the ".n3" from http://www.w3.org/2000/10/swap/log.n3#. Also,

• rdf:is was used in RDF/XML to indicate that the subject o an anonymous node was exacty the given RDF forumula. This is like a property except it infact causes the graph nodes to be the same. it is now http://www.w3.org/2000/10/swap/log#is> as I couln't just put it into the rdf namespace.

• the rdf:resource, rdf:about attribiutes, etc., used to be used without namespaces. They arenow used WITH the namespace RDF/XML generation.

• the rdf:parseType attribute is now assumed to be a qname, and so log:Quote is used instead of j "Quote", by analogy with "daml:collection". Yes, it a lowercase "q", now, too. ((I suppose it is more like a Property than a Class?))

• -reify now works better, as does -flat. They just list the statements and convert the output at the end of procesing, before syntax generation. You can't put a reification stage into a command pipeline. (To do that, pipe the output of cwm to another version)

BUILTINS

There are some magic proprties added to cwm. They perform limited string comparison operations See the documentation..

Received on Sunday, 20 May 2001 23:20:49 UTC