proposition: Lemma _dest_option_inj {A : Type'} (o1 o2 : option A) : _dest_option o1 = _dest_option o2 -> o1 = o2.
proof: Proof. induction o1; induction o2; simpl; rewrite (@CONSTR_INJ A); intros [e1 [e2 e3]]. rewrite e2. reflexivity. discriminate. discriminate. reflexivity. Qed.
imports: Coq.Logic.ClassicalEpsilon ClassicalFacts PropExtensionalityFacts Lia PeanoNat ProofIrrelevance