English
If Y is CommGroup, LocallyConstant X Y inherits a CommGroup structure with pointwise commutativity of multiplication.
Русский
Если Y — комм-группа, LocallyConstant X Y наследует CommGroup с точной антифункцией умножения.
LaTeX
$$$\forall f,g:\mathrm{LocallyConstant}(X,Y),\; (f\cdot g)(x) = (g\cdot f)(x).$$$
Lean4
@[to_additive]
instance [CommGroup Y] : CommGroup (LocallyConstant X Y) :=
Function.Injective.commGroup DFunLike.coe DFunLike.coe_injective' rfl (fun _ _ => rfl) (fun _ => rfl) (fun _ _ => rfl)
(fun _ _ => rfl) (fun _ _ => rfl)