import Definitions.Def_CerednikDrinfeld_FormalUpperHalfPlaneCharts set_option autoImplicit false namespace CerednikDrinfeld.FormalOmega.AlgFunctor variable {𝒪 : Type} [CommRing 𝒪] def const (X : Type) : AlgFunctor 𝒪 where obj _ := X map _ x := x map_id _ := rfl map_comp _ _ _ := rfl @[simp] theorem const_map (X : Type) {B : Type} [CommRing B] [Algebra 𝒪 B] {B' : Type} [CommRing B'] [Algebra 𝒪 B'] (φ : B →ₐ[𝒪] B') (x : X) : (const (𝒪 := 𝒪) X).map φ x = x := rfl end CerednikDrinfeld.FormalOmega.AlgFunctor