Hi:

Sorry, I am new to grammars and ANTLR.

The following grammar:

			

			cons:  CONS NAME RBRAC
			

			;
			

			

			attr:  ATTR NAME RBRAC
			

			;
			

			

			lvar:  LVAR NAME RBRAC
			

			;
			

			

			prule:  PRULE NAME RBRAC
			

			;
			

			

			udf: UDF NAME args RBRAC
			

			;
			

			

			afunc: AFUNC NAME args RBRAC
			

			;
			

			

			tdf: TDF NAME args RBRAC
			

			;
			

			

			args: LPAREN (arg (DELIM arg)*)* RPAREN
			

			;
			

			

			arg:  cons
			

			| attr
			

			| INT
			

			| prule
			

			;
			

			

			atom:   INT
			

			| cons
			

			|   attr
			

			|   lvar
			

			|   prule
			

			|   udf
			

			|   tdf
			

			|   afunc
			

			|   LPAREN expr RPAREN
			

			;
			

			

			

			expr:   atom ((PLUS|MINUS|STAR|DIVIDE|CARET|MOD) atom)*
			

			;
			

		

is supported by the following tokens:

			

			NAME: ('a'..'z'|'A'..'Z'|'_')('a'..'z'|'A'..'Z'|' '|'0'..'9'|'_')*;
			

			

				

				MOD: ('M'|'m')('O'|'o')('D'|'d');
				

			
		

As I expect I get a non-deterministic warning from the ANTLR generator, however I thought it would be easy to resolve this in the parser by changing the order of the rules...but I can seem to resolve it. When I try to parse a statement that has a token that should resolve to NAME I get a recognition error that says it has found MOD and it is expecting NAME.

For example the statement below:

a[MOD]/42

Which gives:

			

			RECOGNITION - PARSE FAILED!!
			

			Localized message: expecting NAME, found 'MOD'
			

			line 1:3: expecting NAME, found 'MOD'
			

			at antlr.Parser.match(Parser.java:211)
			

			at ExprParser.attr(ExprParser.java:55)
			

			at ExprParser.atom(ExprParser.java:181)
			

			at ExprParser.expr(ExprParser.java:226)
			

			at Main.main(Main.java:14)
			

		

However, a[fido] MOD 42, parses without error.

How can I change the grammar to parse both cases without error?

Thanks,

Paul