Re: Please make sure the grammar is directly machine consumable. [OK?]

Tim Berners-Lee wrote:
> This is a followup from a discussion between Yosi Scharf, implementer  
> of SPARQL in cwm, currently on vacation,  and Eric P'dH, co-editor of  
> the spec, several weeks ago.
> Yosi has built his implementation of SPARQL from a file which is  
> almost the one generated from the TR, but with a slight tweak to make  
> the file grammar able to be parsed by a predictive parser [1] a  
> simple form of LL(1) recursive descent parser.  I understood that the  
> tweak was editorial in that the it didn't change the language, just  
> the way it was expressed as a context-free grammar.
> A situation in which code can be generated directly from the spec is  
> a very strong position to be in.  I am not aware of any time this has  
> previously happened for a W3C language, but I may be wrong.  As it is  
> demonstrably simple to make the step here I would request it be done  
> at last call stage before the call for implementation at CR.
> [1] 
> LangProc/lp10.pdf
> Tim Berners-Lee


The SPARQL grammar in the editors' working draft [1] is LL(1)
It has been read in and used to generate parsers using standard tools for C, 
C++, Python, Perl using yacker [1] (LALR(1) or LL(1) depending on the tool). 
The grammar has also been used to generate an LL(1) Java parser.

Please let us know whether this response addresses your comment
to your satisfaction.



Received on Thursday, 13 October 2005 12:43:56 UTC