- From: Seaborne, Andy <andy.seaborne@hp.com>
- Date: Tue, 15 Feb 2005 17:02:26 +0000
- To: Alberto Reggiori <alberto@asemantics.com>
- CC: "'RDF Data Access Working Group'" <public-rdf-dawg@w3.org>
Thanks for the note - for now I have made some changes for publication.
For this week's publication the state is:
1/ BOUND(?x) - no change
2/ Left as AND for now.
3/ Just OPTIONAL, not []
(note that OPTIONAL can take a {} pattern or a plain triple pattern -
restricting to just {} would be OK).
4/ No change to functions/casting/builtins although this does look like it can
be simplified - it just requires more time than is available before publication.
5/ WITH done.
6/ Clause order unchanged
Andy
Alberto Reggiori wrote:
> Andy,
>
> for the record, here are our answers/input to your syntax issues
>
> On Feb 11, 2005, at 10:02 PM, Seaborne, Andy wrote:
>
>
>>This is about tuning the current syntax, post-WD2 publication, not
>>redesigning the whole thing.
>>
>>1/ Bound
>>
>>This is special because it tests the variable, not the value. It's
>>the only
>>case where this happens.
>>
>>The suggestion (PatH) was to make this different. In other
>>programming languages, there is just a plain function like many other
>>library functions. It returns a value (a boolean) like any other
>>function.
>>
>>Options:
>>1a/ BOUND(?x) -- as the current grammar
>
>
> +1 for current form in the grammar
>
>
>>1b/ BOUND[?x] -- different grouping
>>
>>Anything with a colon in it will look like a qname.
>>
>>BOUND ?x is dangerous as it does not express the tight binding nature
>>of
>>this operator: "BOUND ?x && ?y" is strange.
>>
>>I prefer "BOUND(?x)" -- leave as is.
>>BOUND[] as a one-off is over doing it.
>>
>>2/ AND
>>
>>AND is a special keyword that starts constraints (SUCH THAT would be
>>better
>>but its two words). Currently in the grammar it is required because
>>?x-?y is unclear : can be "?x binary minus ?y" or two expressions "?x"
>>then "unary minus ?y"
>
>
> please keep AND for this round still
>
>
>>Proposal: use [] to mark constraints (see below).
>>
>>3/ OPTIONALS
>>
>>There are two syntactic forms "OPTIONAL" and "[]"
>>
>>Proposal: just the OPTIONAL form, freeing up [] for constraints.
>
>
> ok to drop [] and use only OPTIONAL keyword
>
>
>>4/ Functions , casting and specials.
>> &ex:foo() , xsd:byte(23) , isBlank(?x)
>
>
> we are neutral about this one
>
>
>>5/ LOAD => WITH
>>
>>The word "LOAD" suggests, to some people, a permanent change to the
>>database which is a wrong implication. DaveB suggested changing the
>>word to "WITH". I have done this change (rq23 and the tests).
>
>
> ok for WITH change
>
>
>>6/ Clause order
>>
>>The current order is:
>>
>>BASE
>>PREFIX
>>SELECT
>>WITH
>>FROM
>>WHERE
>>LIMIT
>>
>>which is a mixed style. It would make sense to have WITH and FROM
>>before SELECT (declarations first) and have LIMIT before WHERE
>>(modifier to SELECT). It has confused some RDQL users that FROM comes
>>after SELECT.
>
>
> ok for given order - but please add few lines explaining BASE keyword
> in the prolog, still only mentioned into grammar/bnf in ver. 1.207
>
>
> Yours
>
> Alberto
>
> -
> Alberto Reggiori, @Semantics S.R.L.
> www.asemantics.com
>
Received on Tuesday, 15 February 2005 17:03:27 UTC