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