diff options
Diffstat (limited to 'theories')
| -rw-r--r-- | theories/Logic/FunctionalExtensionality.v | 3 | ||||
| -rw-r--r-- | theories/Program/Combinators.v | 12 |
2 files changed, 4 insertions, 11 deletions
diff --git a/theories/Logic/FunctionalExtensionality.v b/theories/Logic/FunctionalExtensionality.v index ac95ddd0c..82b04d132 100644 --- a/theories/Logic/FunctionalExtensionality.v +++ b/theories/Logic/FunctionalExtensionality.v @@ -221,13 +221,12 @@ Tactic Notation "extensionality" "in" hyp(H) := (* If we [subst H], things break if we already have another equation of the form [_ = H] *) destruct Heq; rename H_out into H. -(** Eta expansion follows from extensionality. *) +(** Eta expansion is built into Coq. *) Lemma eta_expansion_dep {A} {B : A -> Type} (f : forall x : A, B x) : f = fun x => f x. Proof. intros. - extensionality x. reflexivity. Qed. diff --git a/theories/Program/Combinators.v b/theories/Program/Combinators.v index 90db10ef1..237d878bf 100644 --- a/theories/Program/Combinators.v +++ b/theories/Program/Combinators.v @@ -22,15 +22,13 @@ Open Scope program_scope. Lemma compose_id_left : forall A B (f : A -> B), id ∘ f = f. Proof. intros. - unfold id, compose. - symmetry. apply eta_expansion. + reflexivity. Qed. Lemma compose_id_right : forall A B (f : A -> B), f ∘ id = f. Proof. intros. - unfold id, compose. - symmetry ; apply eta_expansion. + reflexivity. Qed. Lemma compose_assoc : forall A B C D (f : A -> B) (g : B -> C) (h : C -> D), @@ -47,9 +45,7 @@ Hint Rewrite <- @compose_assoc : core. Lemma flip_flip : forall A B C, @flip A B C ∘ flip = id. Proof. - unfold flip, compose. intros. - extensionality x ; extensionality y ; extensionality z. reflexivity. Qed. @@ -57,9 +53,7 @@ Qed. Lemma prod_uncurry_curry : forall A B C, @prod_uncurry A B C ∘ prod_curry = id. Proof. - simpl ; intros. - unfold prod_uncurry, prod_curry, compose. - extensionality x ; extensionality y ; extensionality z. + intros. reflexivity. Qed. |