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