- From: Andy Seaborne <andy.seaborne@epimorphics.com>
- Date: Tue, 14 Sep 2010 12:01:30 +0100
- To: Axel Polleres <axel.polleres@deri.org>
- CC: SPARQL Working Group <public-rdf-dawg@w3.org>
On 14/09/10 11:15, Axel Polleres wrote:
>> The other definitions need to work with GROUP BY which hides the non-key
>> variables variables. To do this, it would seem easier to define the
>> concept recursively, not declaratively.
>
> my idea was to define it recusrively over the syntax
No problem with that but that's not how the syntax works e.g. OPTIONAL
isn't a binary operator, it's a syntax element that appears in a group.
It's the translation to the algebra and LeftJoin that makes it a
binary operator.
The definition for "potentially bound" needs to mention a "group" (the
thing between {}) and accumulate the bound variables through the syntax
elements that appear in a group.
Andy
Received on Tuesday, 14 September 2010 11:02:06 UTC