diff options
| -rw-r--r-- | theories/Init/Tactics.v | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/theories/Init/Tactics.v b/theories/Init/Tactics.v index 50653c4200..d822a45c50 100644 --- a/theories/Init/Tactics.v +++ b/theories/Init/Tactics.v @@ -18,6 +18,7 @@ Require Import Logic. - H:~A |- ~B gives H: B |- A - H: A |- B gives |- ~A - H: A |- ~B gives H: B |- ~A + - H:False leads to a resolved subgoal. Moreover, negations may be in unfolded forms, and A or B may live in Type *) @@ -46,7 +47,7 @@ Ltac contradict H := match type of H with | (~_) => neg H | (_->False) => neg H - | _ => pos H + | _ => (elim H;fail) || pos H end. (* Transforming a negative goal [ H:~A |- ~B ] into a positive one [ B |- A ]*) @@ -62,7 +63,7 @@ Ltac absurd_hyp H := let T := type of H in absurd T. -(* A useful complement to contradict. Here H : A and G allows to conclude ~A *) +(* A useful complement to contradict. Here H:A while G allows to conclude ~A *) Ltac false_hyp H G := let T := type of H in absurd T; [ apply G | assumption ]. |