English
Similarly for MonoidAlgebra, the bialgebra structure is inherited from A; the counit and comultiplication are defined componentwise.
Русский
Аналогично для MonoidAlgebra; биалгебраическая структура наследуется от A; counit и comul задаются по компонентам.
LaTeX
$$MonoidAlgebra.instBialgebra R A M$$
Lean4
/-- If `f : M → N` is a monoid hom, then `AddMonoidAlgebra.mapDomain f` is a bialgebra hom between
their monoid algebras. -/
@[simps]
noncomputable def mapDomainBialgHom (f : M →+ N) : R[M] →ₐc[R] R[N]
where
__ := mapDomainAlgHom R R f
map_smul' m x := by simp
counit_comp := by ext; simp
map_comp_comul := by ext; simp