let id = Tacticals.id_tac
let injection = DiscriminationTactics.injection_tac
let intros = PrimitiveTactics.intros_tac
+let inversion = Inversion.inversion_tac
let lapply = FwdSimplTactic.lapply_tac
let left = IntroductionTactics.left_tac
let letin = PrimitiveTactics.letin_tac