`sig
external ( +! ) : Gmp.Z.t -> Gmp.Z.t -> Gmp.Z.t = "_mlgmp_z_add"
external ( -! ) : Gmp.Z.t -> Gmp.Z.t -> Gmp.Z.t = "_mlgmp_z_sub"
external ( *! ) : Gmp.Z.t -> Gmp.Z.t -> Gmp.Z.t = "_mlgmp_z_mul"
external ( /! ) : Gmp.Z.t -> Gmp.Z.t -> Gmp.Z.t = "_mlgmp_z_fdiv_q"
external ( %! ) : Gmp.Z.t -> Gmp.Z.t -> Gmp.Z.t = "_mlgmp_z_fdiv_r"
val ( <! ) : Gmp.Z.t -> Gmp.Z.t -> bool
val ( <=! ) : Gmp.Z.t -> Gmp.Z.t -> bool
val ( =! ) : Gmp.Z.t -> Gmp.Z.t -> bool
val ( >=! ) : Gmp.Z.t -> Gmp.Z.t -> bool
val ( >! ) : Gmp.Z.t -> Gmp.Z.t -> bool
val ( <>! ) : Gmp.Z.t -> Gmp.Z.t -> bool
end`