lFalse :: Ord a => Maybe a -> Set a -> Op2 (Skel a)
prllFalse c scs sk0 sk1 = mkOp (Prll False) (go sk0) (go sk1)
  where
    go   = subst (substMember (scs, mAct c) Act)

c
prllFalse :: Ord a => Maybe a -> Set a -> Op2 (Skel a)
prllFalse c scs sk0 sk1 = mkOp (Prll False) (go sk0) (go sk1)
  where
    go   = subst (substMember (scs, mAct c) Act)
prllFalse c scs sk0 sk1 = mkOp (Prll False) (go sk0) (go sk1)
  where
    go   = subst (substMember (scs, mAct c) Act)