Lemmas about functors out of product categories. #
@[simp]
theorem
CategoryTheory.Bifunctor.map_id
{C : Type u₁}
{D : Type u₂}
{E : Type u₃}
[Category.{v₁, u₁} C]
[Category.{v₂, u₂} D]
[Category.{v₃, u₃} E]
(F : Functor (C × D) E)
(X : C)
(Y : D)
:
@[simp]
theorem
CategoryTheory.Bifunctor.map_id_comp
{C : Type u₁}
{D : Type u₂}
{E : Type u₃}
[Category.{v₁, u₁} C]
[Category.{v₂, u₂} D]
[Category.{v₃, u₃} E]
(F : Functor (C × D) E)
(W : C)
{X Y Z : D}
(f : X ⟶ Y)
(g : Y ⟶ Z)
:
F.map (Prod.mkHom (CategoryStruct.id W) (CategoryStruct.comp f g)) = CategoryStruct.comp (F.map (Prod.mkHom (CategoryStruct.id W) f)) (F.map (Prod.mkHom (CategoryStruct.id W) g))
@[simp]
theorem
CategoryTheory.Bifunctor.map_comp_id
{C : Type u₁}
{D : Type u₂}
{E : Type u₃}
[Category.{v₁, u₁} C]
[Category.{v₂, u₂} D]
[Category.{v₃, u₃} E]
(F : Functor (C × D) E)
(X Y Z : C)
(W : D)
(f : X ⟶ Y)
(g : Y ⟶ Z)
:
F.map (Prod.mkHom (CategoryStruct.comp f g) (CategoryStruct.id W)) = CategoryStruct.comp (F.map (Prod.mkHom f (CategoryStruct.id W))) (F.map (Prod.mkHom g (CategoryStruct.id W)))
@[simp]
theorem
CategoryTheory.Bifunctor.diagonal
{C : Type u₁}
{D : Type u₂}
{E : Type u₃}
[Category.{v₁, u₁} C]
[Category.{v₂, u₂} D]
[Category.{v₃, u₃} E]
(F : Functor (C × D) E)
(X X' : C)
(f : X ⟶ X')
(Y Y' : D)
(g : Y ⟶ Y')
:
CategoryStruct.comp (F.map (Prod.mkHom (CategoryStruct.id X) g)) (F.map (Prod.mkHom f (CategoryStruct.id Y'))) = F.map (Prod.mkHom f g)
@[simp]
theorem
CategoryTheory.Bifunctor.diagonal'
{C : Type u₁}
{D : Type u₂}
{E : Type u₃}
[Category.{v₁, u₁} C]
[Category.{v₂, u₂} D]
[Category.{v₃, u₃} E]
(F : Functor (C × D) E)
(X X' : C)
(f : X ⟶ X')
(Y Y' : D)
(g : Y ⟶ Y')
:
CategoryStruct.comp (F.map (Prod.mkHom f (CategoryStruct.id Y))) (F.map (Prod.mkHom (CategoryStruct.id X') g)) = F.map (Prod.mkHom f g)