Dear,

i have some question about CFG, my code look like this.

pNf returns [int value]

: e=atom ('^'z=atom

{ $value = xxx ;}

|'!' {$value = yyy ;})?

;

so i want to use '^' as a Power sign

and '!' as a Factorial sign.

what should i do with xxx and yyy parts?

Best

Teerakarn T.