[Moose-dev] Re: Anyone can explain this PParser behaviour?

Le 1 févr. 2016 à 16:32, Thierry Goubier <thierry.goubier(a)gmail.com&gt; a écrit : 2016-02-01 16:29 GMT+01:00 Anne Etien <anne.etien(a)univ-lille1.fr <mailto:anne.etien@univ-lille1.fr>>: > Le 1 févr. 2016 à 08:09, stepharo <stepharo(a)free.fr <mailto:stepharo@free.fr>> a écrit : > >>> >>> Where? because I spent a couple of hours I only found SQL92 >> >> http://savage.net.au/SQL/ <http://savage.net.au/SQL/> >> >> SQL-92, -99, -2003 > > Excellent! > Thanks I will archive that. I am not an expert in grammar, but I don’t see on this page the rules relative to function or even to select query.

First one, just a search on SELECT in the web page: <query specification>  <http://savage.net.au/SQL/sql-92.bnf.html#xref-query specification> ::= SELECT  <http://savage.net.au/SQL/sql-92.bnf.html#xref-SELECT>[ <set quantifier> <http://savage.net.au/SQL/sql-92.bnf.html#set quantifier> ] <select list> <http://savage.net.au/SQL/sql-92.bnf.html#select list> <table expression> <http://savage.net.au/SQL/sql-92.bnf.html#table expression> Thierry Anne > >> >>>> But the point wasn't that; what a LALR/LR parser gives you is a >>>> grammar ambiguity and conflicts... PetitParser will happily take your >>>> grammar ans you will only discover when parsing something that it >>>> doesn't do what you would like. >>>> >>>> (The reference citation of Aho and Ullman is ... it may be difficult >>>> to determine what the language is). >>>> >>>> So since you have a grammar, use LALR to check it. >>> >>> But as I said we do not have it. >> >> You do have a PEG grammar in your PetitParser efforts, since you have been working on it. From far, those grammars are very much like other grammars... just that the parser generator behave differently when you have conflicts and ambiguity. >> >> Thierry >> _______________________________________________ >> Moose-dev mailing list >> Moose-dev(a)list.inf.unibe.ch <mailto:Moose-dev@list.inf.unibe.ch> >> https://www.list.inf.unibe.ch/listinfo/moose-dev <https://www.list.inf.unibe.ch/listinfo/moose-dev> > > _______________________________________________ > Moose-dev mailing list > Moose-dev(a)list.inf.unibe.ch <mailto:Moose-dev@list.inf.unibe.ch> > https://www.list.inf.unibe.ch/listinfo/moose-dev <https://www.list.inf.unibe.ch/listinfo/moose-dev> _______________________________________________ Moose-dev mailing list Moose-dev(a)list.inf.unibe.ch <mailto:Moose-dev@list.inf.unibe.ch> https://www.list.inf.unibe.ch/listinfo/moose-dev <https://www.list.inf.unibe.ch/listinfo/moose-dev> _______________________________________________ Moose-dev mailing list Moose-dev(a)list.inf.unibe.ch <mailto:Moose-dev@list.inf.unibe.ch> https://www.list.inf.unibe.ch/listinfo/moose-dev <https://www.list.inf.unibe.ch/listinfo/moose-dev>