proposition: Lemma rpred_zify (R : ringType) (S : subringClosed R) (e : zifyRing R) : rval e \in S.
proof: Proof. by rewrite zifyRingE rpred_int. Qed.
imports: mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat choice seq) mathcomp(fintype finfun bigop order ssralg ssrnum ssrint)