{X : Type} (f : X -> X) := {x : X & f x = x}. Global Instance ishprop_fix_wconst {X : Type} (f : X -> X) {wc : WeaklyConstant f} : IsHProp ( f). Proof. apply hprop_inhabited_contr; intros [x0 p0]. refine (contr_equiv' {x:X & f x0 = x} _); unfold . apply equiv_functor_sigma_id. intros x. apply equiv_concat_l. apply wconst. Defined.
Require Import HoTT.Basics HoTT.Types. Require Import Extensions Factorization. Require Import Truncations.Core Modalities.Modality.