- From: Axel Polleres <axel.polleres@deri.org>
- Date: Sat, 19 Sep 2009 13:52:24 +0100
- To: "RIF (E-mail)" <public-rif-wg@w3.org>
Please check [1,2,3]. best, Axel Begin forwarded message: > From: Axel Polleres <axel.polleres@deri.org> > Date: 19 September 2009 13:50:54 GMT+01:00 > To: Carlos Damásio <cd@di.fct.unl.pt> > Cc: <public-rif-comments@w3.org> > Subject: Re: EBNF grammar of presentation syntax > > Dear Carlos, > > Thanks for spotting this. We have updated the EBNF productions in > RIF FLD and BLD to only > allow NCNames (instead of arbitrary unicode strings) for localnames, > Prefix names, > Variable names and Profiles names, cf. [1,2,3] > > Please acknowledge receipt of this email to <mailto:public-rif-comments@w3.org > > > (replying to this email should suffice). In your acknowledgment > please let us > know whether or not you are satisfied with the working group's > response to your > comment. > > with best regards, > Axel > > 1. http://www.w3.org/2005/rules/wiki/FLD#EBNF_Grammar_for_the_Presentation_Syntax_of_RIF-FLD > 2. http://www.w3.org/2005/rules/wiki/BLD#EBNF_Grammar_for_the_Presentation_Syntax_of_RIF-BLD_.28Informative.29 > 3. http://www.w3.org/2005/rules/wiki/DTB#Shortcuts_for_Constants_in_RIF.27s_Presentation_Syntax > > > > On 9 Sep 2009, at 16:54, Carlos Damásio wrote: > >> Dear all, >> >> >> In first place, my congratulations to this nice and necessary work. >> I have just started playing around with Prolog parsers for RIF and >> realized that theEBNF grammar is ambiguous, as noticed before by Axel >> (see http://lists.w3.org/Archives/Public/public-rif-wg/2009Aug/0003.html >> ). >> >> I found very problematic the Name and Var productions which use >> Unicode Strings which are not delimited. For instance the fragment, >> >> Document( >> Dialect( anasty ) dialect ))Base( <http://www.dot.com> ) >> ) >> >> What is the appropriate parsing of this Document? Where does >> Dialect end? >> Even for this >> >> Document( >> Dialect(FOL)Base( <http://www.dot.com> ) >> ) >> >> a possible parsing according to the grammar is to understand this >> as a single dialect declaration "FOL)Base( <http://www.dot.com> ". >> >> I even think that Vars are more problematic because they can appear >> in sequences like >> >> atom(?x?y ?z) >> >> How many vars are there? 1(a var named "x?y ?z), 2( a var named "x? >> y" and other named "z") or 3? >> >> The same applies to UNITERMs like this >> >> atom( ?x->y->z) >> >> A possible way out is to say that some special characters are not >> allowed in Names and use escaped chars for spaces, question marks, >> "->", etc. The exact set of non allowed sequences is to be carefully >> defined because of possible interactions with other grammar >> productions. >> >> Best regards, >> >> Carlos >> >> >> >> > > -- > Dr. Axel Polleres > Digital Enterprise Research Institute, National University of > Ireland, Galway > email: axel.polleres@deri.org url: http://www.polleres.net/ > > > -- Dr. Axel Polleres Digital Enterprise Research Institute, National University of Ireland, Galway email: axel.polleres@deri.org url: http://www.polleres.net/
Received on Saturday, 19 September 2009 12:53:05 UTC