From 7cfc4e5146be5666419451bdd516f1f3f264d24a Mon Sep 17 00:00:00 2001 From: Enrico Tassi Date: Sun, 25 Jan 2015 14:42:51 +0100 Subject: Imported Upstream version 8.5~beta1+dfsg --- test-suite/bugs/closed/1614.v | 21 +++++++++++++++++++++ 1 file changed, 21 insertions(+) create mode 100644 test-suite/bugs/closed/1614.v (limited to 'test-suite/bugs/closed/1614.v') diff --git a/test-suite/bugs/closed/1614.v b/test-suite/bugs/closed/1614.v new file mode 100644 index 00000000..6bc165d4 --- /dev/null +++ b/test-suite/bugs/closed/1614.v @@ -0,0 +1,21 @@ +Require Import Ring. +Require Import ArithRing. + +Fixpoint eq_nat_bool (x y : nat) {struct x} : bool := +match x, y with +| 0, 0 => true +| S x', S y' => eq_nat_bool x' y' +| _, _ => false +end. + +Theorem eq_nat_bool_implies_eq : forall x y, eq_nat_bool x y = true -> x = y. +Proof. +induction x; destruct y; simpl; intro H; try (reflexivity || inversion H). +apply IHx in H; rewrite H; reflexivity. +Qed. + +Add Ring MyNatSRing : natSRth (decidable eq_nat_bool_implies_eq). + +Goal 0 = 0. + ring. +Qed. -- cgit v1.2.3