diff options
Diffstat (limited to 'test-suite/bugs/closed/4725.v')
-rw-r--r-- | test-suite/bugs/closed/4725.v | 38 |
1 files changed, 38 insertions, 0 deletions
diff --git a/test-suite/bugs/closed/4725.v b/test-suite/bugs/closed/4725.v new file mode 100644 index 00000000..fd5e0fb6 --- /dev/null +++ b/test-suite/bugs/closed/4725.v @@ -0,0 +1,38 @@ +Require Import EquivDec Equivalence List Program. +Require Import Relation_Definitions. +Import ListNotations. +Generalizable All Variables. + +Fixpoint removeV `{eqDecV : @EqDec V eqV equivV}`(x : V) (l : list V) : list V +:= + match l with + | nil => nil + | y::tl => if (equiv_dec x y) then removeV x tl else y::(removeV x tl) + end. + +Lemma remove_le {V:Type}{eqV:relation V}{equivV:@Equivalence V eqV}{eqDecV : +@EqDec V eqV equivV} (xs : list V) (x : V) : + length (removeV x xs) < length (x :: xs). + Proof. Admitted. + +(* Function version *) +Set Printing Universes. + +Require Import Recdef. + +Function nubV {V:Type}{eqV:relation V}{equivV:@Equivalence V eqV}{eqDecV : +@EqDec V eqV equivV} (l : list V) { measure length l} := + match l with + | nil => nil + | x::xs => x :: @nubV V eqV equivV eqDecV (removeV x xs) + end. +Proof. intros. apply remove_le. Qed. + +(* Program version *) + +Program Fixpoint nubV `{eqDecV : @EqDec V eqV equivV} (l : list V) + { measure (@length V l) lt } := + match l with + | nil => nil + | x::xs => x :: @nubV V eqV equivV eqDecV (removeV x xs) _ + end. |