Fneg_compute@{} q : - (' q) = ' (Frac.neg _ q) := 1. Global Instance Fmult@{} : Mult F. Proof. refine (F_rec2 (fun x y => ' (Frac.ml _ x y)) _). intros. apply path. apply Frac.ml_respect;trivial. Defined.
Require Import HoTT.HIT.quotient. Require Import Import Frac.