I'm having trouble generating ASTs for lists. I want these lists to be a flexible as possible... I've got something like:

			

			class psrString extends Parser;
			

			

			options { buildAST = true; }
			

			

			complex
			

			: COMPLEX
			

			| FLOAT
			

			;
			

			

			variant
			

			: (OPENSQ!)? (complex  ((COMMA^)? complex )*)) (CLOSESQ!)? ;
			

			

			class Scanner extends Lexer;
			

			

			options { filter=WS; }
			

			

			FLOAT : ('-'|'+')? FLT
			

			((('-'|'+') FLT)? 'i' {$setType(COMPLEX);} )? ;
			

			

			COMMA : ',' ;
			

			OPENSQ : '[' ;
			

			CLOSESQ : ']' ;
			

			

			protected FLT : ( (D)+ ('.' (D)*)? | '.' (D)+ ) ( ('e'|'E') ('-'|'+')? (D)+ )? ;
			

			protected D : '0' .. '9' ;
			

			protected WS : ' ' | ' ' | '
			

			' {newline();} | '
			

			' '
			

			' {newline();} ;
			

			

		

Now, if there happens to be a COMMA, as in [1,2,3,4] , it is parsed and the AST is created fine... however, if the COMMAs are left out, as in [1 2 3 4] , then the AST only contains the first item (i.e. 1 ).

Can anyone give me a hint about how to handle this?

thanks,
Darrell