fact: Definition Zmatch T (n : Z) f g : T := match n with Zpos p => f p | Zneg n => g n end.
imports: mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat div seq) mathcomp(path choice fintype tuple finset bigop order) mathcomp(ssralg zmodp ssrnum ssrint) CoqEAL(hrel param refinements pos)