proposition: Lemma move_wplus_wminus sz (a b c: word sz): a ^+ b = c <-> a = c ^- b.
proof: Proof. split; intro. + rewrite <- H. rewrite wminus_def. rewrite <- wplus_assoc. rewrite wminus_inv. rewrite wplus_wzero_1. reflexivity. + rewrite H. rewrite wminus_def. rewrite <- wplus_assoc. rewrite wplus_comm with (x:= ^~b). rewrite wminus_inv. rewrite wplus_wzero_1. reflexivity. Qed.
imports: Coq.Classes.Morphisms Coq.Classes.Morphisms_Prop Coq.Classes.Equivalence Coq.Arith.PeanoNat Coq.ZArith.BinInt  Coq.Arith.Arith Coq.NArith.NArith Coq.Bool.Bool Coq.ZArith.ZArith Coq.Logic.Eqdep_dec Coq.Logic.EqdepFacts Coq.Program.Tactics Coq.Program.Equality Coq.setoid_ring.Ring Coq.setoid_ring.Ring_polynom bbv.Nomega bbv.ZLib bbv.NatLib bbv.NLib bbv.N_Z_nat_conversions bbv.DepEq bbv.DepEqNat bbv.ReservedNotations Coq.micromega.Lia