Mathlib Map

Theorems · Theorem · category theory

CategoryTheory.ConcreteCategory.hom_ext

∀ {C : Type u} [inst : CategoryTheory.Category.{v, u} C] {FC : C → C → Type u_1} {CC : C → Type w}
  [inst_1 : (X Y : C) → FunLike (FC X Y) (CC X) (CC Y)] [inst_2 : CategoryTheory.ConcreteCategory C FC] {X Y : C}
  (f g : X ⟶ Y),
  (∀ (x : CC X), (CategoryTheory.ConcreteCategory.hom f) x = (CategoryTheory.ConcreteCategory.hom g) x) → f = g

In any concrete category, we can test equality of morphisms by pointwise evaluations.

Defined in
Mathlib.CategoryTheory.ConcreteCategory.Basic
Cited by
48 results in Mathlib
Foundations
Depth 18 from the axioms · uses Quot.sound
Assumes
CategoryTheory.CategoryFunLikeCategoryTheory.ConcreteCategory

Around this declaration

Dashed lines are statement dependencies; solid lines are citations in proofs.

Cites8

Mathlib declarations this one mentions in its statement or cites explicitly in its proof. Plumbing is filtered out.

Cited by48

Results whose statement or proof uses this declaration.