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Diffstat (limited to 'theories/Init')
| -rw-r--r-- | theories/Init/Datatypes.v | 11 |
1 files changed, 11 insertions, 0 deletions
diff --git a/theories/Init/Datatypes.v b/theories/Init/Datatypes.v index 75bf27702e..78d0110ae7 100644 --- a/theories/Init/Datatypes.v +++ b/theories/Init/Datatypes.v @@ -221,6 +221,17 @@ Proof. split; intros; apply CompOpp_inj; rewrite CompOpp_involutive; auto. Qed. +(** The [CompSpec] inductive will be used to relate a [compare] function + (returning a comparison answer) and some equality and order predicates. + Interest: [CompSpec] behave nicely with [destruct]. *) + +Inductive CompSpec {A} (eq lt : A->A->Prop)(x y:A) : comparison -> Prop := + | CompEq : eq x y -> CompSpec eq lt x y Eq + | CompLt : lt x y -> CompSpec eq lt x y Lt + | CompGt : lt y x -> CompSpec eq lt x y Gt. +Hint Constructors CompSpec. + + (** Identity *) Definition ID := forall A:Type, A -> A. |