cancellable invariants are contractive

theories/base_logic/lib/cancelable_invariants.v

@@ -28,10 +28,12 @@ Section proofs.
   Global Instance cinv_own_timeless γ p : TimelessP (cinv_own γ p).
   Proof. rewrite /cinv_own; apply _. Qed.
 
+  Global Instance cinv_contractive N γ : Contractive (cinv N γ).
+  Proof. solve_contractive. Qed.
   Global Instance cinv_ne N γ : NonExpansive (cinv N γ).
-  Proof. solve_proper. Qed.
+  Proof. exact: contractive_ne. Qed.
   Global Instance cinv_proper N γ : Proper ((≡) ==> (≡)) (cinv N γ).
-  Proof. apply (ne_proper _). Qed.
+  Proof. exact: ne_proper. Qed.
 
   Global Instance cinv_persistent N γ P : PersistentP (cinv N γ P).
   Proof. rewrite /cinv; apply _. Qed.