On 29/11/15 11:33, james anderson wrote:
> good morning;
>> On 2015-11-29, at 11:33, Andy Seaborne <> wrote:
>> […]
>>> Is there any theoretical or technical obstacle to this?
>> There's no obstacle.  A Google Summer of Code project added this to Apache Jena this year and it'll be in the next release.
>> It follows the design you gave:
> while a quite reasonable extension proposal and one which leads one to wonder why it was left out of the 1.1 recommendation, there are questions.

Many reasons:

No standardized syntax and MIME type.
   SPARQL 1.1 predates standardized Trig and N-quads - indeed,
   "RDF Dataset" was not in RDF - it was only in SPARQL.

Limited resources. Limited time.  Limited interest.

> - what identifier does arq intend to us in the service description to indicate its support
> - as a matter of interoperability, is the elided graph case in the “complete form” example really in instance of the grammar which appears later in the document? given the example, this reader would have expected a production of the form
>     ( 'GRAPH’ )? VarOrIri '{' TriplesTemplate? ‘}’

i.e. "TriG-with-variables", rather than SPARQL Update quad blocks.

> - which end does the elision serve?

Thank you to Google for funding the work of Qihong Lin.

Getting the project finished in time matters. GSoC projects are fixed 

It is also desirable for it to be a simple extension for everyone but it 
is not incremental to add and remain LL(1) AKA easy parsing (it's 3 
separate additional local LL(2) changes I think); obviously it is 
possible to do convert LL(2) to LL(1) but it needs rewriting all the 
template rules, making it not a just local change in one rule.

Not everyone is using the same parser generator (ARQ uses javacc so lots 
of bells and whistles here like variable local lookahead).  The GRAPH 
implementation is a local change in one part of the grammar.

When in standards mode (default), the grammar remains what is in the 
spec, not something supposedly equivalent.


> best regards, from berlin,
> ---
> james anderson | |

Received on Sunday, 29 November 2015 15:04:53 UTC