Definition coopstep g c m c' m' :=
   CMin_corestep g c m c' m'.

(* Specifications: *)
Lemma cmin_coopstep_not_at_external: forall ge m q m' q', coopstep ge q m q' m' -> CMin_at_external q = None.
Lemma cmin_coopstep_not_halted : forall ge m q m' q', coopstep ge q m q' m' -> CMin_halted q = None.