fact: Definition int_to_pos (z : int) : pos := insubd pos1 (int_to_nat z).
imports: HB(structures) ZArith mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat div seq zmodp) mathcomp(path choice fintype tuple finset ssralg ssrnum bigop ssrint) CoqEAL(hrel param refinements)