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Diffstat (limited to 'src/Util/Relations.v')
| -rw-r--r-- | src/Util/Relations.v | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/src/Util/Relations.v b/src/Util/Relations.v index 8ab045cfe..7dc654ec3 100644 --- a/src/Util/Relations.v +++ b/src/Util/Relations.v @@ -51,3 +51,9 @@ Qed. Global Instance eq_eta_Reflexive {T} : Reflexive (fun x y : T => x = y) | 1 := eq_Reflexive. + +Global Instance Symmetric_not {T:Type} (R:T->T->Prop) + {SymmetricR:Symmetric R} : Symmetric (fun a b => not (R a b)). +Proof. cbv [Symmetric] in *; repeat intro; eauto. Qed. + +Lemma not_exfalso (P:Prop) (H:P->False) : not P. auto with nocore. Qed.
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