lean2/hott/init/pointed.hlean
Floris van Doorn 8db4676c46 feat(hott): various changes and additions in the HoTT library
Add more theorems about mapping cylinders, fibers, truncated 2-quotient, truncated univalence, pre/postcomposition with an iso in a precategory.

renamings: equiv.refl -> equiv.rfl and equiv_eq <-> equiv_eq'
2016-05-06 14:27:27 -07:00

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/-
Copyright (c) 2016 Floris van Doorn. All rights reserved.
Released under Apache 2.0 license as described in the file LICENSE.
Authors: Floris van Doorn
The definition of pointed types. This file is here to avoid circularities in the import graph
-/
prelude
import init.trunc
open eq equiv is_equiv is_trunc
structure pointed [class] (A : Type) :=
(point : A)
structure pType :=
(carrier : Type)
(Point : carrier)
notation `Type*` := pType
namespace pointed
attribute pType.carrier [coercion]
variables {A : Type}
definition pt [reducible] [unfold 2] [H : pointed A] := point A
definition Point [reducible] [unfold 1] (A : Type*) := pType.Point A
abbreviation carrier [unfold 1] (A : Type*) := pType.carrier A
protected definition Mk [constructor] {A : Type} (a : A) := pType.mk A a
protected definition MK [constructor] (A : Type) (a : A) := pType.mk A a
protected definition mk' [constructor] (A : Type) [H : pointed A] : Type* :=
pType.mk A (point A)
definition pointed_carrier [instance] [constructor] (A : Type*) : pointed A :=
pointed.mk (Point A)
end pointed
open pointed
section
universe variable u
structure ptrunctype (n : trunc_index) extends trunctype.{u} n, pType.{u}
definition is_trunc_ptrunctype [instance] {n : ℕ₋₂} (X : ptrunctype n)
: is_trunc n (ptrunctype.to_pType X) :=
trunctype.struct X
end
notation n `-Type*` := ptrunctype n
abbreviation pSet [parsing_only] := 0-Type*
notation `Set*` := pSet
namespace pointed
protected definition ptrunctype.mk' [constructor] (n : trunc_index)
(A : Type) [pointed A] [is_trunc n A] : n-Type* :=
ptrunctype.mk A _ pt
protected definition pSet.mk [constructor] := @ptrunctype.mk (-1.+1)
protected definition pSet.mk' [constructor] := ptrunctype.mk' (-1.+1)
definition ptrunctype_of_trunctype [constructor] {n : trunc_index} (A : n-Type) (a : A) : n-Type* :=
ptrunctype.mk A _ a
definition ptrunctype_of_pType [constructor] {n : trunc_index} (A : Type*) (H : is_trunc n A)
: n-Type* :=
ptrunctype.mk A _ pt
definition pSet_of_Set [constructor] (A : Set) (a : A) : Set* :=
ptrunctype.mk A _ a
definition pSet_of_pType [constructor] (A : Type*) (H : is_set A) : Set* :=
ptrunctype.mk A _ pt
attribute ptrunctype._trans_of_to_pType ptrunctype.to_pType ptrunctype.to_trunctype [unfold 2]
end pointed
/- pointed maps -/
structure pmap (A B : Type*) :=
(to_fun : A → B)
(resp_pt : to_fun (Point A) = Point B)
namespace pointed
abbreviation respect_pt [unfold 3] := @pmap.resp_pt
notation `map₊` := pmap
infix ` →* `:30 := pmap
attribute pmap.to_fun [coercion]
end pointed open pointed
/- pointed homotopies -/
structure phomotopy {A B : Type*} (f g : A →* B) :=
(homotopy : f ~ g)
(homotopy_pt : homotopy pt ⬝ respect_pt g = respect_pt f)
namespace pointed
variables {A B : Type*} {f g : A →* B}
infix ` ~* `:50 := phomotopy
abbreviation to_homotopy_pt [unfold 5] := @phomotopy.homotopy_pt
abbreviation to_homotopy [coercion] [unfold 5] (p : f ~* g) : Πa, f a = g a :=
phomotopy.homotopy p
/- pointed equivalences -/
structure pequiv (A B : Type*) extends equiv A B, pmap A B
attribute pequiv._trans_of_to_pmap pequiv._trans_of_to_equiv pequiv.to_pmap pequiv.to_equiv
[unfold 3]
infix ` ≃* `:25 := pequiv
attribute pequiv.to_pmap [coercion]
attribute pequiv.to_is_equiv [instance]
end pointed