if I have defined something like that
COMMAND = "HI" | "HOW" | "ARE" | "YOU"
How can i say "if u match something that is not a COMMAND"?..
I tried with this one
[^COMMAND]
But didn't work..
As far as I can tell this is not possible with (current) JFlex.
We would need an effective tempered negative lookahead: ((?!bad).)*
There are two ways to do a negative lookahead in JFlex:
x / !(y [^]*)
(match x if not followed by y in the lookahead).x / [^y]|y[^z]
(match if x is followed by something that is !a or a!b.Otherwise, you may get some ideas from this answer (specifically the lookaround alternatives): https://stackoverflow.com/a/37988661/8291949