proposition: Lemma fdeg_eq0I m : fdeg m = 0%N -> m = 1%M.
proof: Proof. rewrite fdegE => /size0nil z_m; apply/eqP. by rewrite -val_eqE /= z_m fm1. Qed.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat) mathcomp(seq path choice finset fintype finfun) mathcomp(tuple bigop ssralg ssrint ssrnum) xfinmap