eqHsBang (HsUserBang u1 b1)   (HsUserBang u2 b2)   = u1==u2 && b1==b2
eqHsBang (HsUserBang u1 b1)   (HsUserBang u2 b2)   = u1==u2 && b1==b2
eqHsBang (HsUserBang u1 b1)   (HsUserBang u2 b2)   = u1==u2 && b1==b2