feat(hott/algebra/precategory): general cleanup in precategories, define uncurrying functor

This commit is contained in:
Floris van Doorn 2015-02-27 00:45:21 -05:00
parent 05cfb21c4c
commit 219f7ae11a
12 changed files with 247 additions and 209 deletions

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@ -22,8 +22,7 @@ namespace category
definition Category_hset [reducible] : Category :=
Category.mk hset category_hset
--RENAME AND CLEANUP
definition set_category_equiv_iso (a b : Category_hset) : (a ≅ b) = (a ≃ b) := sorry
definition isomorphic_hset_eq_equiv (a b : Category_hset) : (a ≅ b) = (a ≃ b) := sorry
end hset
namespace ops

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@ -25,7 +25,7 @@ namespace category
precategory.rec_on C groupoid.mk H
definition groupoid_of_1_type.{l} (A : Type.{l})
[H : is_trunc (succ zero) A] : groupoid.{l l} A :=
[H : is_trunc 1 A] : groupoid.{l l} A :=
groupoid.mk
(λ (a b : A), a = b)
(λ (a b : A), have ish : is_hset (a = b), from is_trunc_eq nat.zero a b, ish)

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@ -27,7 +27,7 @@ namespace category
-- input ⟶ using \--> (this is a different arrow than \-> (→))
infixl [parsing-only] `⟶`:25 := precategory.hom
namespace hom
infixl `⟶` := precategory.hom -- if you open this namespace, hom a b is printed as a ⟶ b
infixl `⟶`:25 := precategory.hom -- if you open this namespace, hom a b is printed as a ⟶ b
end hom
abbreviation hom := @precategory.hom
@ -39,28 +39,83 @@ namespace category
abbreviation id_right := @precategory.id_right
section basic_lemmas
variables {ob : Type} [C : precategory ob]
variables {a b c d : ob} {h : c ⟶ d} {g : hom b c} {f f' : hom a b} {i : a ⟶ a}
include C
variables {ob : Type} [C : precategory ob]
variables {a b c d : ob} {h : c ⟶ d} {g : hom b c} {f f' : hom a b} {i : a ⟶ a}
include C
definition id [reducible] := ID a
definition id [reducible] := ID a
definition id_compose (a : ob) : ID a ∘ ID a = ID a := !id_left
definition id_compose (a : ob) : ID a ∘ ID a = ID a := !id_left
definition left_id_unique (H : Π{b} {f : hom b a}, i ∘ f = f) : i = id :=
calc i = i ∘ id : id_right
... = id : H
definition left_id_unique (H : Π{b} {f : hom b a}, i ∘ f = f) : i = id :=
calc i = i ∘ id : id_right
... = id : H
definition right_id_unique (H : Π{b} {f : hom a b}, f ∘ i = f) : i = id :=
calc i = id ∘ i : id_left
... = id : H
definition right_id_unique (H : Π{b} {f : hom a b}, f ∘ i = f) : i = id :=
calc i = id ∘ i : id_left
... = id : H
definition homset [reducible] (x y : ob) : hset :=
hset.mk (hom x y) _
definition is_hprop_eq_hom [instance] : is_hprop (f = f') :=
!is_trunc_eq
definition homset [reducible] (x y : ob) : hset :=
hset.mk (hom x y) _
definition is_hprop_eq_hom [instance] : is_hprop (f = f') :=
!is_trunc_eq
end basic_lemmas
context squares
parameters {ob : Type} [C : precategory ob]
local infixl `⟶`:25 := @precategory.hom ob C
local infixr `∘` := @precategory.comp ob C _ _ _
definition compose_squares {xa xb xc ya yb yc : ob}
{xg : xb ⟶ xc} {xf : xa ⟶ xb} {yg : yb ⟶ yc} {yf : ya ⟶ yb}
{wa : xa ⟶ ya} {wb : xb ⟶ yb} {wc : xc ⟶ yc}
(xyab : wb ∘ xf = yf ∘ wa) (xybc : wc ∘ xg = yg ∘ wb)
: wc ∘ (xg ∘ xf) = (yg ∘ yf) ∘ wa :=
calc
wc ∘ (xg ∘ xf) = (wc ∘ xg) ∘ xf : assoc
... = (yg ∘ wb) ∘ xf : xybc
... = yg ∘ (wb ∘ xf) : assoc
... = yg ∘ (yf ∘ wa) : xyab
... = (yg ∘ yf) ∘ wa : assoc
set_option unifier.max_steps 30000
definition compose_squares_2x2 {xa xb xc ya yb yc za zb zc : ob}
{xg : xb ⟶ xc} {xf : xa ⟶ xb} {yg : yb ⟶ yc} {yf : ya ⟶ yb} {zg : zb ⟶ zc} {zf : za ⟶ zb}
{va : ya ⟶ za} {vb : yb ⟶ zb} {vc : yc ⟶ zc} {wa : xa ⟶ ya} {wb : xb ⟶ yb} {wc : xc ⟶ yc}
(xyab : wb ∘ xf = yf ∘ wa) (xybc : wc ∘ xg = yg ∘ wb)
(yzab : vb ∘ yf = zf ∘ va) (yzbc : vc ∘ yg = zg ∘ vb)
: (vc ∘ wc) ∘ (xg ∘ xf) = (zg ∘ zf) ∘ (va ∘ wa) :=
calc
(vc ∘ wc) ∘ (xg ∘ xf) = vc ∘ (wc ∘ (xg ∘ xf)) : (assoc vc wc (xg ∘ xf))⁻¹ᵖ
... = vc ∘ ((yg ∘ yf) ∘ wa) : {compose_squares xyab xybc}
... = (vc ∘ (yg ∘ yf)) ∘ wa : assoc vc (yg ∘ yf) wa
... = ((zg ∘ zf) ∘ va) ∘ wa : {compose_squares yzab yzbc}
... = (zg ∘ zf) ∘ (va ∘ wa) : (assoc (zg ∘ zf) va wa)⁻¹ᵖ
set_option unifier.max_steps 20000
definition square_precompose {xa xb xc yb yc : ob}
{xg : xb ⟶ xc} {yg : yb ⟶ yc} {wb : xb ⟶ yb} {wc : xc ⟶ yc}
(H : wc ∘ xg = yg ∘ wb) (xf : xa ⟶ xb) : wc ∘ xg ∘ xf = yg ∘ wb ∘ xf :=
calc
wc ∘ xg ∘ xf = (wc ∘ xg) ∘ xf : assoc
... = (yg ∘ wb) ∘ xf : H
... = yg ∘ wb ∘ xf : assoc
definition square_postcompose {xb xc yb yc yd : ob}
{xg : xb ⟶ xc} {yg : yb ⟶ yc} {wb : xb ⟶ yb} {wc : xc ⟶ yc}
(H : wc ∘ xg = yg ∘ wb) (yh : yc ⟶ yd) : (yh ∘ wc) ∘ xg = (yh ∘ yg) ∘ wb :=
calc
(yh ∘ wc) ∘ xg = yh ∘ wc ∘ xg : assoc
... = yh ∘ yg ∘ wb : H
... = (yh ∘ yg) ∘ wb : assoc
definition square_prepostcompose {xa xb xc yb yc yd : ob}
{xg : xb ⟶ xc} {yg : yb ⟶ yc} {wb : xb ⟶ yb} {wc : xc ⟶ yc}
(H : wc ∘ xg = yg ∘ wb) (yh : yc ⟶ yd) (xf : xa ⟶ xb)
: (yh ∘ wc) ∘ (xg ∘ xf) = (yh ∘ yg) ∘ (wb ∘ xf) :=
square_precompose (square_postcompose H yh) xf
end squares
structure Precategory : Type :=
(carrier : Type)

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@ -95,7 +95,7 @@ namespace category
: precategory (obC × obD) :=
precategory.mk (λ a b, hom (pr1 a) (pr1 b) × hom (pr2 a) (pr2 b))
(λ a b, !is_trunc_prod)
(λ a b c g f, (pr1 g ∘ pr1 f , pr2 g ∘ pr2 f) )
(λ a b c g f, (pr1 g ∘ pr1 f , pr2 g ∘ pr2 f))
(λ a, (id, id))
(λ a b c d h g f, pair_eq !assoc !assoc )
(λ a b f, prod_eq !id_left !id_left )
@ -153,21 +153,21 @@ namespace category
section precategory_functor
open morphism functor nat_trans
definition precategory_functor [instance] [reducible] (C D : Precategory)
definition precategory_functor [instance] [reducible] (D C : Precategory)
: precategory (functor C D) :=
precategory.mk (λa b, nat_trans a b)
(λ a b, @nat_trans.to_hset C D a b)
(λ a b, @is_hset_nat_trans C D a b)
(λ a b c g f, nat_trans.compose g f)
(λ a, nat_trans.id)
(λ a b c d h g f, !nat_trans.assoc)
(λ a b f, !nat_trans.id_left)
(λ a b f, !nat_trans.id_right)
definition Precategory_functor [reducible] (C D : Precategory) : Precategory :=
precategory.Mk (precategory_functor C D)
definition Precategory_functor [reducible] (D C : Precategory) : Precategory :=
precategory.Mk (precategory_functor D C)
definition Precategory_functor_rev [reducible] (C D : Precategory) : Precategory :=
Precategory_functor D C
-- definition Precategory_functor_rev [reducible] (C D : Precategory) : Precategory :=
-- Precategory_functor D C
/- we prove that if a natural transformation is pointwise an iso, then it is an iso -/
variables {C D : Precategory} {F G : C ⇒ D} (η : F ⟹ G) [iso : Π(a : C), is_iso (η a)]
@ -199,13 +199,13 @@ namespace category
apply is_hset.elim
end
definition nat_trans_is_iso.mk : is_iso η :=
definition nat_trans_iso.mk : is_iso η :=
is_iso.mk (nat_trans_left_inverse η) (nat_trans_right_inverse η)
end precategory_functor
namespace ops
infixr `^c`:35 := Precategory_functor_rev
infixr `^c`:35 := Precategory_functor
infixr `×f`:30 := product.prod_functor
infixr `ᵒᵖᶠ`:(max+1) := opposite.opposite_functor
end ops

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@ -28,7 +28,7 @@ namespace functor
-- The following lemmas will later be used to prove that the type of
-- precategories forms a precategory itself
protected definition compose (G : functor D E) (F : functor C D) : functor C E :=
protected definition compose [reducible] (G : functor D E) (F : functor C D) : functor C E :=
functor.mk
(λ x, G (F x))
(λ a b f, G (F f))
@ -41,6 +41,11 @@ namespace functor
infixr `∘f`:60 := compose
protected definition id [reducible] {C : Precategory} : functor C C :=
mk (λa, a) (λ a b f, f) (λ a, idp) (λ a b c f g, idp)
protected definition ID [reducible] (C : Precategory) : functor C C := id
definition functor_eq_mk'' {F₁ F₂ : C → D} {H₁ : Π(a b : C), hom a b → hom (F₁ a) (F₁ b)}
{H₂ : Π(a b : C), hom a b → hom (F₂ a) (F₂ b)} (id₁ id₂ comp₁ comp₂)
(pF : F₁ = F₂) (pH : pF ▹ H₁ = H₂)
@ -71,39 +76,17 @@ namespace functor
(pH : Π(a b : C) (f : hom a b), H₁ a b f = H₂ a b f)
: functor.mk F H₁ id₁ comp₁ = functor.mk F H₂ id₂ comp₂ :=
functor_eq_mk'' id₁ id₂ comp₁ comp₂ idp
(eq_of_homotopy (λc, eq_of_homotopy (λc', eq_of_homotopy (λf, pH c c' f))))
(eq_of_homotopy (λc, eq_of_homotopy (λc', eq_of_homotopy (pH c c'))))
definition functor_eq_mk {F₁ F₂ : C ⇒ D} : Π(p : obF F₁ obF F₂),
(Π(a b : C) (f : hom a b), transport (λF, hom (F a) (F b)) (eq_of_homotopy p) (F₁ f) = F₂ f)
→ F₁ = F₂ :=
functor.rec_on F₁ (λO₁ H₁ id₁ comp₁, functor.rec_on F₂ (λO₂ H₂ id₂ comp₂ p q, !functor_eq_mk' q))
-- protected definition congr
-- {C : Precategory} {D : Precategory}
-- (F : C → D)
-- (foo2 : Π ⦃a b : C⦄, hom a b → hom (F a) (F b))
-- (foo3a foo3b : Π (a : C), foo2 (ID a) = ID (F a))
-- (foo4a foo4b : Π {a b c : C} (g : @hom C C b c) (f : @hom C C a b),
-- foo2 (g ∘ f) = foo2 g ∘ foo2 f)
-- (p3 : foo3a = foo3b) (p4 : @foo4a = @foo4b)
-- : functor.mk F foo2 foo3a @foo4a = functor.mk F foo2 foo3b @foo4b
-- :=
-- begin
-- apply (eq.rec_on p3), intros,
-- apply (eq.rec_on p4), intros,
-- apply idp,
-- end
functor.rec_on F₁ (λO₁ H₁ id₁ comp₁, functor.rec_on F₂ (λO₂ H₂ id₂ comp₂ p, !functor_eq_mk'))
protected definition assoc {A B C D : Precategory} (H : functor C D) (G : functor B C) (F : functor A B) :
H ∘f (G ∘f F) = (H ∘f G) ∘f F :=
!functor_eq_mk_constant (λa b f, idp)
protected definition id {C : Precategory} : functor C C :=
mk (λa, a) (λ a b f, f) (λ a, idp) (λ a b c f g, idp)
protected definition ID (C : Precategory) : functor C C := id
protected definition id_left (F : functor C D) : id ∘f F = F :=
functor.rec_on F (λF1 F2 F3 F4, !functor_eq_mk_constant (λa b f, idp))
@ -173,7 +156,7 @@ namespace category
namespace ops
abbreviation PreCat := Precat_of_strict_cats
abbreviation SPreCat := Precat_of_strict_cats
--attribute precat_of_strict_precats [instance]
end ops

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@ -63,17 +63,17 @@ namespace morphism
(Hl : g ∘ f = id) (Hr : f ∘ g' = id) : g = g' :=
by rewrite [-(id_right g), -Hr, assoc, Hl, id_left]
theorem retraction_eq_intro [H : is_section f] (H2 : f ∘ h = id) : retraction_of f = h
:= left_inverse_eq_right_inverse !retraction_compose H2
theorem retraction_eq_intro [H : is_section f] (H2 : f ∘ h = id) : retraction_of f = h :=
left_inverse_eq_right_inverse !retraction_compose H2
theorem section_eq_intro [H : is_retraction f] (H2 : h ∘ f = id) : section_of f = h
:= (left_inverse_eq_right_inverse H2 !compose_section)⁻¹
theorem section_eq_intro [H : is_retraction f] (H2 : h ∘ f = id) : section_of f = h :=
(left_inverse_eq_right_inverse H2 !compose_section)⁻¹
theorem inverse_eq_intro_right [H : is_iso f] (H2 : f ∘ h = id) : f⁻¹ = h
:= left_inverse_eq_right_inverse !inverse_compose H2
theorem inverse_eq_intro_right [H : is_iso f] (H2 : f ∘ h = id) : f⁻¹ = h :=
left_inverse_eq_right_inverse !inverse_compose H2
theorem inverse_eq_intro_left [H : is_iso f] (H2 : h ∘ f = id) : f⁻¹ = h
:= (left_inverse_eq_right_inverse H2 !compose_inverse)⁻¹
theorem inverse_eq_intro_left [H : is_iso f] (H2 : h ∘ f = id) : f⁻¹ = h :=
(left_inverse_eq_right_inverse H2 !compose_inverse)⁻¹
theorem section_of_eq_retraction_of (f : a ⟶ b) [Hl : is_section f] [Hr : is_retraction f] :
retraction_of f = section_of f :=

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@ -20,7 +20,7 @@ namespace nat_trans
attribute natural_map [coercion]
protected definition compose (η : G ⟹ H) (θ : F ⟹ G) : F ⟹ H :=
protected definition compose [reducible] (η : G ⟹ H) (θ : F ⟹ G) : F ⟹ H :=
nat_trans.mk
(λ a, η a ∘ θ a)
(λ a b f,
@ -33,6 +33,12 @@ namespace nat_trans
infixr `∘n`:60 := compose
protected definition id [reducible] {C D : Precategory} {F : functor C D} : nat_trans F F :=
mk (λa, id) (λa b f, !id_right ⬝ !id_left⁻¹)
protected definition ID [reducible] {C D : Precategory} (F : functor C D) : nat_trans F F :=
id
local attribute is_hprop_eq_hom [instance]
definition nat_trans_eq_mk' {η₁ η₂ : Π (a : C), hom (F a) (G a)}
(nat₁ : Π (a b : C) (f : hom a b), G f ∘ η₁ a = η₁ b ∘ F f)
@ -48,12 +54,6 @@ namespace nat_trans
η₃ ∘n (η₂ ∘n η₁) = (η₃ ∘n η₂) ∘n η₁ :=
nat_trans_eq_mk (λa, !assoc)
protected definition id {C D : Precategory} {F : functor C D} : nat_trans F F :=
mk (λa, id) (λa b f, !id_right ⬝ !id_left⁻¹)
protected definition ID {C D : Precategory} (F : functor C D) : nat_trans F F :=
id
protected definition id_left (η : F ⟹ G) : id ∘n η = η :=
nat_trans_eq_mk (λa, !id_left)
@ -79,7 +79,7 @@ namespace nat_trans
end
set_option apply.class_instance false
protected definition to_hset : is_hset (F ⟹ G) :=
definition is_hset_nat_trans : is_hset (F ⟹ G) :=
begin
apply is_trunc_is_equiv_closed, apply (equiv.to_is_equiv !sigma_char),
apply is_trunc_sigma,

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@ -42,9 +42,8 @@ open is_equiv equiv
namespace functor
open prod nat_trans
variables {C D E : Precategory}
definition functor_curry_ob (F : C ×c D ⇒ E) (c : C) : E ^c D :=
variables {C D E : Precategory} (F : C ×c D ⇒ E) (G : C ⇒ E ^c D)
definition functor_curry_ob [reducible] (c : C) : E ^c D :=
functor.mk (λd, F (c,d))
(λd d' g, F (id, g))
(λd, !respect_id)
@ -52,9 +51,9 @@ namespace functor
F (id, g' ∘ g) = F (id ∘ id, g' ∘ g) : {(id_compose c)⁻¹}
... = F ((id,g') ∘ (id, g)) : idp
... = F (id,g') ∘ F (id, g) : respect_comp F qed)
local abbreviation Fob := @functor_curry_ob
definition functor_curry_mor (F : C ×c D ⇒ E) ⦃c c' : C⦄ (f : c ⟶ c') : Fob F c ⟹ Fob F c' :=
definition functor_curry_hom ⦃c c' : C⦄ (f : c ⟶ c') : Fob F c ⟹ Fob F c' :=
nat_trans.mk (λd, F (f, id))
(λd d' g, proof calc
F (id, g) ∘ F (f, id) = F (id ∘ f, g ∘ id) : respect_comp F
@ -64,36 +63,146 @@ namespace functor
... = F (f ∘ id, id ∘ g) : {(id_left g)⁻¹}
... = F (f, id) ∘ F (id, g) : (respect_comp F (f, id) (id, g))⁻¹ᵖ
qed)
local abbreviation Fhom := @functor_curry_hom
local abbreviation Fmor := @functor_curry_mor
definition functor_curry_mor_def (F : C ×c D ⇒ E) ⦃c c' : C⦄ (f : c ⟶ c') (d : D) :
(Fmor F f) d = F (f, id) := idp
definition functor_curry_hom_def ⦃c c' : C⦄ (f : c ⟶ c') (d : D) :
(Fhom F f) d = homF F (f, id) := idp
definition functor_curry_id (F : C ×c D ⇒ E) (c : C) : Fmor F (ID c) = nat_trans.id :=
definition functor_curry_id (c : C) : Fhom F (ID c) = nat_trans.id :=
nat_trans_eq_mk (λd, respect_id F _)
definition functor_curry_comp (F : C ×c D ⇒ E) ⦃c c' c'' : C⦄ (f' : c' ⟶ c'') (f : c ⟶ c')
: Fmor F (f' ∘ f) = Fmor F f' ∘n Fmor F f :=
definition functor_curry_comp ⦃c c' c'' : C⦄ (f' : c' ⟶ c'') (f : c ⟶ c')
: Fhom F (f' ∘ f) = Fhom F f' ∘n Fhom F f :=
nat_trans_eq_mk (λd, calc
natural_map (Fmor F (f' ∘ f)) d = F (f' ∘ f, id) : functor_curry_mor_def
... = F (f' ∘ f, id ∘ id) : {(id_compose d)⁻¹}
... = F ((f',id) ∘ (f, id)) : idp
... = F (f',id) ∘ F (f, id) : respect_comp F
... = natural_map ((Fmor F f') ∘ (Fmor F f)) d : idp)
natural_map (Fhom F (f' ∘ f)) d = F (f' ∘ f, id) : functor_curry_hom_def
... = F (f' ∘ f, id ∘ id) : {(id_compose d)⁻¹}
... = F ((f',id) ∘ (f, id)) : idp
... = F (f',id) ∘ F (f, id) : respect_comp F
... = natural_map ((Fhom F f') ∘ (Fhom F f)) d : idp)
--respect_comp F (g, id) (f, id)
definition functor_curry (F : C ×c D ⇒ E) : C ⇒ E ^c D :=
definition functor_curry [reducible] : C ⇒ E ^c D :=
functor.mk (functor_curry_ob F)
(functor_curry_mor F)
(functor_curry_hom F)
(functor_curry_id F)
(functor_curry_comp F)
definition functor_uncurry_ob [reducible] (p : C ×c D) : E :=
obF (G p.1) p.2
local abbreviation Gob := @functor_uncurry_ob
definition is_equiv_functor_curry : is_equiv (@functor_curry C D E) := sorry
definition functor_uncurry_hom ⦃p p' : C ×c D⦄ (f : hom p p') : Gob G p ⟶ Gob G p' :=
homF (obF G p'.1) f.2 ∘ natural_map (homF G f.1) p.2
local abbreviation Ghom := @functor_uncurry_hom
definition functor_uncurry_id (p : C ×c D) : Ghom G (ID p) = id :=
calc
Ghom G (ID p) = homF (obF G p.1) id ∘ natural_map (homF G id) p.2 : idp
... = id ∘ natural_map (homF G id) p.2 : ap (λx, x ∘ _) (respect_id (obF G p.1) p.2)
... = id ∘ natural_map nat_trans.id p.2 : {respect_id G p.1}
... = id : id_compose
definition functor_uncurry_comp ⦃p p' p'' : C ×c D⦄ (f' : p' ⟶ p'') (f : p ⟶ p')
: Ghom G (f' ∘ f) = Ghom G f' ∘ Ghom G f :=
calc
Ghom G (f' ∘ f)
= homF (obF G p''.1) (f'.2 ∘ f.2) ∘ natural_map (homF G (f'.1 ∘ f.1)) p.2 : idp
... = (homF (obF G p''.1) f'.2 ∘ homF (obF G p''.1) f.2)
∘ natural_map (homF G (f'.1 ∘ f.1)) p.2 : {respect_comp (obF G p''.1) f'.2 f.2}
... = (homF (obF G p''.1) f'.2 ∘ homF (obF G p''.1) f.2)
∘ natural_map (homF G f'.1 ∘ homF G f.1) p.2 : {respect_comp G f'.1 f.1}
... = (homF (obF G p''.1) f'.2 ∘ homF (obF G p''.1) f.2)
∘ (natural_map (homF G f'.1) p.2 ∘ natural_map (homF G f.1) p.2) : idp
... = (homF (obF G p''.1) f'.2 ∘ homF (obF G p''.1) f.2)
∘ (natural_map (homF G f'.1) p.2 ∘ natural_map (homF G f.1) p.2) : idp
... = (homF (obF G p''.1) f'.2 ∘ natural_map (homF G f'.1) p'.2)
∘ (homF (obF G p'.1) f.2 ∘ natural_map (homF G f.1) p.2) :
square_prepostcompose (!naturality⁻¹ᵖ) _ _
... = Ghom G f' ∘ Ghom G f : idp
definition functor_uncurry [reducible] : C ×c D ⇒ E :=
functor.mk (functor_uncurry_ob G)
(functor_uncurry_hom G)
(functor_uncurry_id G)
(functor_uncurry_comp G)
-- open pi
-- definition functor_eq_mk'1 {F₁ F₂ : C → D} {H₁ : Π(a b : C), hom a b → hom (F₁ a) (F₁ b)}
-- {H₂ : Π(a b : C), hom a b → hom (F₂ a) (F₂ b)} (id₁ id₂ comp₁ comp₂)
-- (pF : F₁ = F₂) (pH : Π(a b : C) (f : hom a b), pF ▹ (H₁ a b f) = H₂ a b f)
-- : functor.mk F₁ H₁ id₁ comp₁ = functor.mk F₂ H₂ id₂ comp₂ :=
-- functor_eq_mk'' id₁ id₂ comp₁ comp₂ pF
-- (eq_of_homotopy (λc, eq_of_homotopy (λc', eq_of_homotopy (λf,
-- begin
-- apply concat, rotate_left 1, exact (pH c c' f),
-- apply concat, rotate_left 1,
-- exact (pi_transport_constant pF (H₁ c c') f),
-- apply (apD10' f),
-- apply concat, rotate_left 1,
-- exact (pi_transport_constant pF (H₁ c) c'),
-- apply (apD10' c'),
-- apply concat, rotate_left 1,
-- exact (pi_transport_constant pF H₁ c),
-- apply idp
-- end))))
-- definition functor_eq_mk1 {F₁ F₂ : C ⇒ D} : Π(p : obF F₁ = obF F₂),
-- (Π(a b : C) (f : hom a b), transport (λF, hom (F a) (F b)) p (F₁ f) = F₂ f)
-- → F₁ = F₂ :=
-- functor.rec_on F₁ (λO₁ H₁ id₁ comp₁, functor.rec_on F₂ (λO₂ H₂ id₂ comp₂ p, !functor_eq_mk'1))
--set_option pp.notation false
definition functor_uncurry_functor_curry : functor_uncurry (functor_curry F) = F :=
functor_eq_mk (λp, ap (obF F) !prod.eta)
begin
intros (cd, cd', fg),
cases cd with (c,d), cases cd' with (c',d'), cases fg with (f,g),
have H : (functor_uncurry (functor_curry F)) (f, g) = F (f,g),
from calc
(functor_uncurry (functor_curry F)) (f, g) = homF F (id, g) ∘ homF F (f, id) : idp
... = F (id ∘ f, g ∘ id) : respect_comp F (id,g) (f,id)
... = F (f, g ∘ id) : {id_left f}
... = F (f,g) : {id_right g},
rewrite H,
apply sorry
end
--set_option pp.implicit true
definition functor_curry_functor_uncurry : functor_curry (functor_uncurry G) = G :=
begin
fapply functor_eq_mk,
{intro c,
fapply functor_eq_mk,
{intro d, apply idp},
{intros (d, d', g),
have H : homF (functor_curry (functor_uncurry G) c) g = homF (G c) g,
from calc
homF (functor_curry (functor_uncurry G) c) g
= homF (G c) g ∘ natural_map (homF G (ID c)) d : idp
... = homF (G c) g ∘ natural_map (ID (G c)) d
: ap (λx, homF (G c) g ∘ natural_map x d) (respect_id G c)
... = homF (G c) g : id_right,
rewrite H,
-- esimp {idp},
apply sorry
}
},
apply sorry
end
definition equiv_functor_curry : (C ×c D ⇒ E) ≃ (C ⇒ E ^c D) :=
equiv.mk _ !is_equiv_functor_curry
equiv.MK functor_curry
functor_uncurry
functor_curry_functor_uncurry
functor_uncurry_functor_curry
definition functor_prod_flip_ob : C ×c D ⇒ D ×c C :=
functor.mk sorry sorry sorry sorry
definition contravariant_yoneda_embedding : Cᵒᵖ ⇒ set ^c C :=
functor_curry !yoneda.representable_functor
end functor
-- Coq uses unit/counit definitions as basic
-- open yoneda precategory.product precategory.opposite functor morphism

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@ -1,87 +0,0 @@
/-
Copyright (c) 2014 Jakob von Raumer. All rights reserved.
Released under Apache 2.0 license as described in the file LICENSE.
Module: equiv_precomp
Author: Jakob von Raumer
Ported from Coq HoTT
-/
-- This file is nowhere used. Do we want to keep it?
open eq function funext
namespace is_equiv
context
--Precomposition of arbitrary functions with f
definition precompose {A B : Type} (f : A → B) (C : Type) (h : B → C) : A → C := h ∘ f
--Postcomposition of arbitrary functions with f
definition postcompose {A B : Type} (f : A → B) (C : Type) (l : C → A) : C → B := f ∘ l
--Precomposing with an equivalence is an equivalence
definition arrow_equiv_arrow_of_equiv_dom [instance] {A B : Type} (f : A → B) [F : funext] [Hf : is_equiv f] (C : Type)
: is_equiv (precompose f C) :=
adjointify (precompose f C) (λh, h ∘ f⁻¹)
(λh, eq_of_homotopy (λx, ap h (sect f x)))
(λg, eq_of_homotopy (λy, ap g (retr f y)))
--Postcomposing with an equivalence is an equivalence
definition arrow_equiv_arrow_of_equiv_cod [instance] {A B : Type} (f : A → B) [F : funext] [Hf : is_equiv f] (C : Type)
: is_equiv (postcompose f C) :=
adjointify (postcompose f C) (λl, f⁻¹ ∘ l)
(λh, eq_of_homotopy (λx, retr f (h x)))
(λg, eq_of_homotopy (λy, sect f (g y)))
--Conversely, if pre- or post-composing with a function is always an equivalence,
--then that function is also an equivalence. It's convenient to know
--that we only need to assume the equivalence when the other type is
--the domain or the codomain.
private definition isequiv_precompose_eq {A B : Type} (f : A → B) (C D : Type)
(Ceq : is_equiv (precompose f C)) (Deq : is_equiv (precompose f D)) (k : C → D) (h : A → C) :
k ∘ (precompose f C)⁻¹ h = (precompose f D)⁻¹ (k ∘ h) :=
let invD := inv (precompose f D) in
let invC := inv (precompose f C) in
have eq1 : invD (k ∘ h) = k ∘ (invC h),
from calc invD (k ∘ h) = invD (k ∘ (precompose f C (invC h))) : retr (precompose f C) h
... = k ∘ (invC h) : !sect,
eq1⁻¹
definition is_equiv_of_is_equiv_precomp {A B : Type} (f : A → B) (Aeq : is_equiv (precompose f A))
(Beq : is_equiv (precompose f B)) : (is_equiv f) :=
let invA := inv (precompose f A) in
let invB := inv (precompose f B) in
let sect' : f ∘ (invA id) id := (λx,
calc f (invA id x) = (f ∘ invA id) x : idp
... = invB (f ∘ id) x : apD10 (!isequiv_precompose_eq)
... = invB (precompose f B id) x : idp
... = x : apD10 (sect (precompose f B) id))
in
let retr' : (invA id) ∘ f id := (λx,
calc invA id (f x) = precompose f A (invA id) x : idp
... = x : apD10 (retr (precompose f A) id)) in
adjointify f (invA id) sect' retr'
end
end is_equiv
--Bundled versions of the previous theorems
namespace equiv
definition arrow_equiv_arrow_of_equiv_dom [F : funext] {A B C : Type} {eqf : A ≃ B}
: (B → C) ≃ (A → C) :=
let f := to_fun eqf in
let Hf := to_is_equiv eqf in
equiv.mk (is_equiv.precompose f C)
(@is_equiv.arrow_equiv_arrow_of_equiv_dom A B f F Hf C)
definition arrow_equiv_arrow_of_equiv_cod [F : funext] {A B C : Type} {eqf : A ≃ B}
: (C → A) ≃ (C → B) :=
let f := to_fun eqf in
let Hf := to_is_equiv eqf in
equiv.mk (is_equiv.postcompose f C)
(@is_equiv.arrow_equiv_arrow_of_equiv_cod A B f F Hf C)
end equiv

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@ -144,7 +144,11 @@ end funext
open funext
definition eq_of_homotopy {A : Type} {P : A → Type} {f g : Π x, P x} : f g → f = g :=
is_equiv.inv (@apD10 A P f g)
(@apD10 A P f g)⁻¹
definition eq_of_homotopy_id {A : Type} {P : A → Type} (f : Π x, P x)
: eq_of_homotopy (λx : A, idpath (f x)) = idpath f :=
is_equiv.sect apD10 idp
definition eq_of_homotopy2 {A B : Type} {P : A → B → Type}
(f g : Πx y, P x y) : (Πx y, f x y = g x y) → f = g :=
@ -152,5 +156,3 @@ definition eq_of_homotopy2 {A B : Type} {P : A → B → Type}
definition naive_funext_of_ua : naive_funext :=
λ A P f g h, eq_of_homotopy h
exit

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@ -1,23 +0,0 @@
/-
Copyright (c) 2014 Jakob von Raumer. All rights reserved.
Released under Apache 2.0 license as described in the file LICENSE.
Module: truncation
Authors: Jakob von Raumer
-/
open is_trunc
-- Axiomatize the truncation operator as long as we do not have
-- Higher inductive types
axiom truncate (A : Type) (n : trunc_index) : Type
axiom truncate.mk {A : Type} (n : trunc_index) (a : A) : truncate A n
axiom truncate.is_trunc (A : Type) (n : trunc_index) : is_trunc n (truncate A n)
axiom truncate.rec_on {A : Type} {n : trunc_index} {C : truncate A n → Type}
(ta : truncate A n)
[H : Π (ta : truncate A n), is_trunc n (C ta)]
(CC : Π (a : A), C (truncate.mk n a)) : C ta

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@ -17,24 +17,24 @@ namespace is_pointed
variables {A B : Type} (f : A → B)
-- Any contractible type is pointed
protected definition contr [instance] [H : is_contr A] : is_pointed A :=
definition is_pointed_of_is_contr [instance] [H : is_contr A] : is_pointed A :=
is_pointed.mk !center
-- A pi type with a pointed target is pointed
protected definition pi [instance] {P : A → Type} [H : Πx, is_pointed (P x)]
definition is_pointed_pi [instance] {P : A → Type} [H : Πx, is_pointed (P x)]
: is_pointed (Πx, P x) :=
is_pointed.mk (λx, point (P x))
-- A sigma type of pointed components is pointed
protected definition sigma [instance] {P : A → Type} [G : is_pointed A]
definition is_pointed_sigma [instance] {P : A → Type} [G : is_pointed A]
[H : is_pointed (P !point)] : is_pointed (Σx, P x) :=
is_pointed.mk ⟨!point,!point⟩
protected definition prod [H1 : is_pointed A] [H2 : is_pointed B]
definition is_pointed_prod [H1 : is_pointed A] [H2 : is_pointed B]
: is_pointed (A × B) :=
is_pointed.mk (!point,!point)
protected definition loop_space (a : A) : is_pointed (a = a) :=
definition is_pointed_loop_space (a : A) : is_pointed (a = a) :=
is_pointed.mk idp
end is_pointed