Yanfly's Lunatic Damage: Apply State to Self

Hey guys.

Quick question here.... I want to apply a state to user when using an attacking skill.

On the script, I used something like this:

when /customdamage/i
          value+=a.add_state(7);(120 + a.atk * 4 - b.def * 2)*(b.state?(9) ? 0 : 1)*(b.state?(32) ? 0 : 1);

But everytime the skill hits, it says "Nil cannot be coerced into Fixnum"

Is it possible to do this? Thanks.