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Diffstat (limited to 'test-suite/bugs/closed/8432.v')
-rw-r--r-- | test-suite/bugs/closed/8432.v | 39 |
1 files changed, 39 insertions, 0 deletions
diff --git a/test-suite/bugs/closed/8432.v b/test-suite/bugs/closed/8432.v new file mode 100644 index 00000000..844ee126 --- /dev/null +++ b/test-suite/bugs/closed/8432.v @@ -0,0 +1,39 @@ +Require Import Program.Tactics. + +Obligation Tactic := idtac. +Set Universe Polymorphism. + +Inductive paths {A : Type} (a : A) : A -> Type := + idpath : paths a a. + +Inductive Empty : Type :=. +Inductive Unit : Type := tt. +Definition not (A : Type) := A -> Empty. + + Lemma nat_path_O_S (n : nat) (H : paths O (S n)) : Empty. + Proof. refine ( + match H in paths _ i return + match i with + | O => Unit + | S _ => Empty + end + with + | idpath _ => tt + end + ). Defined. + Lemma symmetry {A} (x y : A) (p : paths x y) : paths y x. + Proof. + destruct p. apply idpath. + Defined. + Lemma nat_path_S_O (n : nat) (H : paths (S n) O) : Empty. + Proof. eapply nat_path_O_S. exact (symmetry _ _ H). Defined. +Set Printing Universes. +Program Fixpoint succ_not_zero (n:nat) : not (paths (S n) 0) := +match n as n return not (paths (S n) 0) with +| 0 => nat_path_S_O _ +| S n' => let dummy := succ_not_zero n' in _ +end. +Next Obligation. + intros f _ n dummy H. exact (nat_path_S_O _ H). + Show Universes. +Defined. |