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-rw-r--r-- | theories/Lists/List.v | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/theories/Lists/List.v b/theories/Lists/List.v index c004b156b..fb686151b 100644 --- a/theories/Lists/List.v +++ b/theories/Lists/List.v @@ -969,7 +969,7 @@ Section Map. Lemma in_flat_map : forall (f:A->list B)(l:list A)(y:B), In y (flat_map f l) <-> exists x, In x l /\ In y (f x). - Proof. + Proof using A B. induction l; simpl; split; intros. contradiction. destruct H as (x,(H,_)); contradiction. |