fact: Definition comp_lfun aT vT rT (f : 'Hom(vT, rT)) (g : 'Hom(aT, vT)) := linfun (fun_of_lfun f \o fun_of_lfun g).
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat seq choice) mathcomp(fintype bigop finfun tuple) mathcomp(ssralg matrix mxalgebra zmodp)