Canonical aimg_aspace rT f E := ASpace (@aimg_is_aspace rT f E).Fact vsval_multiplicative K : multiplicative (vsval : subvs_of K -> L).Canonical vsval_rmorphism K := AddRMorphism (vsval_multiplicative K).

Lemma vsval_invf K (w : subvs_of K) : val w^-1 = (vsval w)^-1.