[antlr-interest] Nondeterminism in a simple expression grammar

[jbb at acm.org]

On Fri, 07 May 2004 21:02:15 +0000, Dave Bailey <dave at daveb.net> wrote:
>...
>options { language = "Cpp"; genHashLines = true; }
>class test_parser extends Parser;
>options { k = 3; buildAST = true; }
>
>test : (expr SEMI!)+ EOF! ;
>expr : uexp | bexp ;
>uexp : U^ expr ;
>bexp : ID (B^ (uexp | ID))* ;
>
>class test_lexer extends Lexer;
>options { testLiterals = true; }
>tokens  { U = "U"; B = "B"; }
>SEMI : ';' ;
>WS   : (' '|'\n'{newline();}) {$setType(antlr::Token::SKIP);} ;
>ID   : ('a'..'z'|'A'..'Z')+ ;
>...

instead of 

	bexp : ID (B^ (uexp | ID))* ;

maybe try

	bexp : ID (B^ exp)? ;

(it seemed to work okay for me in java and no k=3 is required)

hope this helps...


 
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