lean2/hott/hit/trunc.hlean

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/-
Copyright (c) 2015 Floris van Doorn. All rights reserved.
Released under Apache 2.0 license as described in the file LICENSE.
Module: hit.trunc
Authors: Floris van Doorn
n-truncation of types.
Ported from Coq HoTT
-/
/- The hit n-truncation is primitive, declared in init.hit. -/
import types.sigma
open is_trunc eq equiv is_equiv function prod sum sigma
namespace trunc
protected definition elim {n : trunc_index} {A : Type} {P : Type}
[Pt : is_trunc n P] (H : A → P) : trunc n A → P :=
trunc.rec H
protected definition elim_on {n : trunc_index} {A : Type} {P : Type} (aa : trunc n A)
[Pt : is_trunc n P] (H : A → P) : P :=
elim H aa
end trunc