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Re: Review of N-triples in test cases

From: Dave Beckett <dave.beckett@bristol.ac.uk>
Date: Mon, 11 Nov 2002 12:13:15 +0000
To: Graham Klyne <GK@NineByNine.org>
Cc: RDF core WG <w3c-rdfcore-wg@w3.org>
Message-ID: <22124.1037016795@hoth.ilrt.bris.ac.uk>

>>>Graham Klyne said:
> 
> I've just looked through the N-triples section of the test cases draft 
> [1].  I think it's fine to publish as WD.  I do have some small comments 
> for consideration,
> 
> [1] http://www.w3.org/2001/08/rdf-test/#ntriples
> 
> ...
> 
> Section 3:
> [[
> NOTE: N-Triples is not an user RDF syntax - it is intended for RDF Core WG 
> testing purposes and checking RDF applications for conformance with the 
> specifications.
> ]]
> 
> I'm not sure what is meant here by "user RDF syntax" -- I could claim the 
> same applies to RDF/XML.  Suggest something like:
> [[
> N-Triples is not recommended for general exchange of RDF data - ...
> ]]

This disclaimer is there because this syntax is primarily for test
cases and has not been designed in particular, to be very easy to use
with for non--US-ASCII, which is a requirement for all new W3C
formats.  Hence the dumb restrictions and verbosity (but clarity) we
have on it that would be removed for a more user-friendly language.
Such a language would be nearer N3 that this.

I've changed this to

 [[
 NOTE: N-Triples is an RDF syntax intended for RDF Core WG 
 testing purposes and checking RDF applications for conformance with the 
 specifications.  The recommended RDF exchange syntax is RDF/XML
 as defined in [RDF-SYNTAX].
 ]]

(maybe subject to more wordsmithing?)


> ...
> 
> Section 3.1:
> 
> [[
> language ::= ( character - ( '.' | ws ) )+
> and containing any allowed xml:lang content as defined in
> http://www.w3.org/TR/REC-xml#sec-lang-tag
> ]]
> 
> The syntax production here is very generalized compared with the RFC3066 
> syntax productions (and RFC1766 before it, as cited by the cited 
> document).  I suggest either:
> (a) don't give any syntax production, just cite the REC-xml section, OR

Funnily, Jeremy suggested removing that citation.


> (b) give a syntax that matches the RFC3066 production, which in ABNF is:
> [[
>     The language tag is composed of one or more parts: A primary language
>     subtag and a (possibly empty) series of subsequent subtags.
> 
>     The syntax of this tag in ABNF [RFC 2234] is:
> 
>      Language-Tag = Primary-subtag *( "-" Subtag )
> 
>      Primary-subtag = 1*8ALPHA
> 
>      Subtag = 1*8(ALPHA / DIGIT)
> 
>     The productions ALPHA and DIGIT are imported from RFC 2234; they
>     denote respectively the characters A to Z in upper or lower case and
>     the digits from 0 to 9.  The character "-" is HYPHEN-MINUS (ABNF:
>     %x2D).
> ]]
> -- http://www.ietf.org/rfc/rfc3066.txt
> 
> (I'm not sure offhand if the XML syntax notation can do the counted 
> sequence productions.)

and Jeremy didn't suggest this.

Personally I'd something nearer the latter.  I'll wait for some more
feedback before changing this.


> 
> Section 3.2:
> 
> Given the restricted use for N-triples, per note in section 3, this 
> paragraph seems out of place:
> [[
> It is recommended but not required that the resulting Unicode character 
> string be made available to applications in UTF-8 encoding.
> ]]
> I suggest dropping it.

It was only a suggestion.

Deleted.


> Section 3.3:
> 
> This read oddly to me:
> [[
> URI references are sequences of US-ASCII character productions as defined 
> in [RFC 2396] or must result in a URI reference after the standard escaping 
> procedure is applied. The procedure is applied when passing the URI 
> reference to a URI resolver. The standard escaping procedure is described 
> in [RFC 2396] using UTF-8 as the character encoding.
> ]]
> 
> Hmmm... when does N-triples call for a URIref to be passed to a resolver?
> 
> I'm not sure exactly what is intended here, but I think it was something 
> like this:
> [[
> URI references are sequences of US-ASCII character productions as defined 
> in [RFC 2396] for a URI character sequence.  Where the original URIref 
> contains characters not allowed in such a sequence, the standard escaping 
> procedure described in [RFC 2396] using UTF-8 as the character encoding is 
> applied, using UTF-8 as the character encoding.
> ]]

I was wondering about linking it [RDF-CONCEPTS] sections?

Changed to your wording.

Dave
Received on Monday, 11 November 2002 07:18:43 EST

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