∀ {C : Type u₁} [inst : CategoryTheory.Category.{v₁, u₁} C] {A : Type u₂} [inst_1 : CategoryTheory.Category.{v₂, u₂} A]
  {B : Type u₃} [inst_2 : CategoryTheory.Category.{v₃, u₃} B] (J : CategoryTheory.GrothendieckTopology C)
  {F : CategoryTheory.Functor A B} [inst_3 : J.HasSheafCompose F],
  CategoryTheory.sheafCompose_map J (CategoryTheory.CategoryStruct.id F) =
    CategoryTheory.CategoryStruct.id (CategoryTheory.sheafCompose J F)