Definition isrigfuntoringdiff (X : rig) : @isrigfun X (rigtoring X) (toringdiff X) := isaddmonoidfuntoringdiff X ,, ismultmonoidfuntoringdiff X.
Require Import UniMath.Algebra.Groups. Require Import UniMath.MoreFoundations.Sets. Require Import UniMath.MoreFoundations.Orders.