W3C home > Mailing lists > Public > public-rdf-dawg@w3.org > October to December 2010

Re: NOT EXISTS {P} = ! (EXISTS {P} ) , yes?

From: Andy Seaborne <andy.seaborne@epimorphics.com>
Date: Wed, 06 Oct 2010 09:01:20 +0100
Message-ID: <4CAC2CD0.10205@epimorphics.com>
To: Axel Polleres <axel.polleres@deri.org>
CC: SPARQL Working Group <public-rdf-dawg@w3.org>


On 05/10/10 21:59, Axel Polleres wrote:
> just to be clear... NOT is just syntactic sugar for !, yes? i.e.

Syntactically, no; functionally yes.

>
> FILTER (NOT EXISTS {P} )  = FILTER ( ! (EXISTS {P} ) ) , yes?

FILTER NOT EXISTS {P}
is legal - this is a syntax issue.

NOT EXISTS is a single token.

! EXISTS is two tokens.

> and likewise for NOT IN...

Same.

> is that observation correct?

http://lists.w3.org/Archives/Public/public-rdf-dawg/2010JulSep/0444.html

> Thanks for clarification,
>
> Axel
>
>
Received on Wednesday, 6 October 2010 08:01:58 GMT

This archive was generated by hypermail 2.3.1 : Tuesday, 26 March 2013 16:15:44 GMT