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

2016-02-01 16:29 GMT+01:00 Anne Etien <anne.etien(a)univ-lille1.fr&gt;: > > Le 1 févr. 2016 à 08:09, stepharo <stepharo(a)free.fr&gt; a écrit : > > > Where? because I spent a couple of hours I only found SQL92 > > > 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%20specification> ::= SELECT <http://savage.net.au/SQL/sql-92.bnf.html#xref-SELECT>[ <set quantifier> <http://savage.net.au/SQL/sql-92.bnf.html#set%20quantifier> ] <select list> <http://savage.net.au/SQL/sql-92.bnf.html#select%20list> <table expression> <http://savage.net.au/SQL/sql-92.bnf.html#table%20expression>

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 > https://www.list.inf.unibe.ch/listinfo/moose-dev > > > _______________________________________________ > Moose-dev mailing list > Moose-dev(a)list.inf.unibe.ch > https://www.list.inf.unibe.ch/listinfo/moose-dev > > > > _______________________________________________ > Moose-dev mailing list > Moose-dev(a)list.inf.unibe.ch > https://www.list.inf.unibe.ch/listinfo/moose-dev > >