Re: Possible grammar problem with decimal numbers

Hi Thomas,

Thank you for your comments.  However, unless I misunderstand, I believe your comments are directed to the SPARQL Working Group [1] and not to the RDF Working Group.  If so, your email should go to public-rdf-dawg-comments@w3.org. 

Regards,
Dave
--
http://about.me/david_wood

[1] http://www.w3.org/2009/sparql/wiki/Main_Page


On Apr 9, 2013, at 13:00, Thomas Visel <TVisel@algebraixdata.com> wrote:

> Gentlemen,
> While verifying our implementation of Sparql, I have encountered what several suspected problems in the grammar.
>  
> 1st Case:  The following production (in http://www.w3.org/TR/sparql11-query/#rUnaryExpression) permits decimal numbers of the following exemplary forms:  ddd.d    ddd.ddd   .ddd  .  Decimals of the form  ddd.  are not permitted.
>  
> [147]
> DECIMAL
> ::=
> [0-9]* '.' [0-9]+
>  
> If this was not the intended result, the right-hand side of the production might better read as
>  
> [0-9]* '.' [0-9]+ | [0-9] '.'
>  
> The original motivation might be the conflicting use of a floating number in the object position of a triple, where a fraction-free float’s decimal point would conflict with the triple’s closing AND ‘.’ mark.
>  
> The implications of leaving [147] as-is is that FILTER [?data > 29.] is not legal, a visible annoyance.
>  
>  
> 2nd Case:  There is a slight inconsistency in treatment of DECIMAL (per above) and DOUBLEs:
>  
> [148]
> DOUBLE
> ::=
> [0-9]+ '.' [0-9]* EXPONENT | '.' ([0-9])+ EXPONENT | ([0-9])+ EXPONENT
>  
> For single precision DECIMAL, the leading digit is optional.  For DOUBLE, a leading digit is mandatory.  Is there a motivation for this difference?
>  
>  
> My regards to the WG for taking 1.1 through to closure.
> 
> Thomas A. Visel
> AlgebraixData, Inc.
> (512) 651-5834
>