∀ {R : Type u_3} {S : Type u_4} {M : Type u_6} [inst : Semiring R] [inst_1 : Semiring S] (f : R →+ S)
  (x : MonoidAlgebra R M), MonoidAlgebra.map f x = MonoidAlgebra.ofCoeff (Finsupp.mapRange ⇑f ⋯ x.coeff)