(*========================================================= A AND A_1 ARE INVERSES INJECTIONS IN A hmap: ==========================================================*)
(* In a qmap, A et A_1 are inverses: *)

Lemma A_1_A :
forall (m:fmap)(k:dim)(z:dart),
inv_hmap m -> succ m k z ->
A_1 m k (A m k z) = z.