RE: comment on JSON-LD 1.0: no @base support

Hi Jeremy,

Thanks for your feedback. We had support for @base in the past but decided
to drop it to decrease the number of ways an IRI can be expressed. Is there
a specific use case that cannot be solved using any of the existing
mechanisms? Or is it just that it would be handy in some cases?

Personally, I'm very concerned about adding yet another mechanism to express
IRIs. We already have:
 
 - document-relative IRIs
 - absolute IRIs
 - terms
 - compact IRIs
 - @vocab as a global prefix for properties and values
   coerced to @vocab

Is it really a problem to express the "custom base" using a prefix? Could
@vocab be used?


> I note that (3, the most powerful mechanism, best supports
> reuse of existing JSON (Zero Edits, most of the time)

There are many things that would help in that regard - the most powerful
technique probably being IRI templates (see ISSUE-108 [1]). But, at the same
time, we must be very careful to not introduce too much variability.
Requiring a developer to keep track of 3 (or more) base IRIs is very
problematic in my opinion.

As you might already noticed we added your request to the agenda of today's
telecon [2]. It's open for everyone, so please feel free to join.


Cheers,
Markus


[1] https://github.com/json-ld/json-ld.org/issues/108
[2] http://lists.w3.org/Archives/Public/public-rdf-wg/2013Feb/0200.html


--
Markus Lanthaler
@markuslanthaler




------------ Original message --------------
From: Jeremy J Carroll [mailto:jjc@syapse.com] 
Sent: Friday, February 22, 2013 10:21 PM
To: public-rdf-comments@w3.org
Subject: comment on JSON-LD 1.0: no @base support


Hi

this is a comment on http://www.w3.org/TR/json-ld-syntax/
http://www.w3.org/TR/2012/WD-json-ld-syntax-20120712/

This is a formal comment, in that I would appreciate a response before
JSON-LD exits last call.

Short form:
  please add an optional attribute @base to be included as a Syntax Token
and Keyword

Long form:

JSON-LD appears to provide two abbreviation mechanisms: prefixing and
relative URIs

The draft provides good support for prefixing; but not much support for
relative URIs, in particular no mechanism corresponding to section 5.1.1 of
RFC 3986.

Three different designs would be:
1) allow an @base name/value pair at the top level of the JSON-LD document
to specify a base URI applicable to the whole document
[simple]

2) allow an @base name/value pair at any level of the JSON-LD document to
specify a base URI applicable to the scope of the document (scoped liked the
@context)
[more powerful]

3) allow an @base inside the context, and to have the same scope as an
@language within the Context
[can be funky when multiple contexts are in separate documents, perhaps each
specifying different @base's with relative URIs …. !!!]


Any one of these would adequately address the comment.

I note that (3, the most powerful mechanism, best supports reuse of existing
JSON (Zero Edits, most of the time)


thanks

Jeremy J. Carroll

Received on Tuesday, 26 February 2013 11:24:21 UTC