proposition: Fact lfun_add0 : left_id zero_lfun add_lfun.
proof: Proof. by move=> f; apply/lfunP=> v; rewrite lfunE /= lfunE add0r. Qed.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat seq choice) mathcomp(fintype bigop finfun tuple) mathcomp(ssralg matrix mxalgebra zmodp)