Merge branch 'dev'
This commit is contained in:
commit
c3b585d03b
17
CHANGELOG.md
17
CHANGELOG.md
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@ -1,6 +1,23 @@
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Changelog
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=========
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Version 1.2.0
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-------------
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This version is mainly a huge refactor.
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I've renamed
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* `distrib` to `isDistributive`
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* `arrowIsSet` to `arrowsAreSets`
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* `ident` to `isIdentity`
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* `assoc` to `isAssociative`
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And added "type-synonyms" for all of these. Their names should now match their
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type. So e.g. `isDistributive` has type `IsDistributive`.
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I've also changed how names are exported in `Functor` to be in line with
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`Category`.
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Version 1.1.0
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-------------
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In this version categories have been refactored - there's now a notion of a raw
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|
|
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@ -16,107 +16,58 @@ open import Cat.Category.Exponential
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open import Cat.Equality
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open Equality.Data.Product
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open Functor
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open IsFunctor
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open Category hiding (_∘_)
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open Functor using (func→ ; func*)
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open Category using (Object ; 𝟙)
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-- The category of categories
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module _ (ℓ ℓ' : Level) where
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private
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module _ {𝔸 𝔹 ℂ 𝔻 : Category ℓ ℓ'} {F : Functor 𝔸 𝔹} {G : Functor 𝔹 ℂ} {H : Functor ℂ 𝔻} where
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private
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eq* : func* (H ∘f (G ∘f F)) ≡ func* ((H ∘f G) ∘f F)
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eq* = refl
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eq→ : PathP
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(λ i → {A B : Object 𝔸} → 𝔸 [ A , B ] → 𝔻 [ eq* i A , eq* i B ])
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(func→ (H ∘f (G ∘f F))) (func→ ((H ∘f G) ∘f F))
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eq→ = refl
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postulate
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eqI
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: (λ i → ∀ {A : Object 𝔸} → eq→ i (𝟙 𝔸 {A}) ≡ 𝟙 𝔻 {eq* i A})
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[ (H ∘f (G ∘f F)) .isFunctor .ident
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≡ ((H ∘f G) ∘f F) .isFunctor .ident
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]
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eqD
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: (λ i → ∀ {A B C} {f : 𝔸 [ A , B ]} {g : 𝔸 [ B , C ]}
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→ eq→ i (𝔸 [ g ∘ f ]) ≡ 𝔻 [ eq→ i g ∘ eq→ i f ])
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[ (H ∘f (G ∘f F)) .isFunctor .distrib
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≡ ((H ∘f G) ∘f F) .isFunctor .distrib
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]
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assc : H ∘f (G ∘f F) ≡ (H ∘f G) ∘f F
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assc = Functor≡ eq* eq→ (IsFunctor≡ eqI eqD)
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assc = Functor≡ refl refl
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module _ {ℂ 𝔻 : Category ℓ ℓ'} {F : Functor ℂ 𝔻} where
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module _ where
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private
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eq* : (func* F) ∘ (func* (identity {C = ℂ})) ≡ func* F
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eq* = refl
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-- lemmm : func→ {C = A} {D = B} (f ∘f identity) ≡ func→ f
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eq→ : PathP
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(λ i →
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{x y : Object ℂ} → Arrow ℂ x y → Arrow 𝔻 (func* F x) (func* F y))
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(func→ (F ∘f identity)) (func→ F)
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eq→ = refl
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postulate
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eqI-r
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: (λ i → {c : Object ℂ} → (λ _ → 𝔻 [ func* F c , func* F c ])
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[ func→ F (𝟙 ℂ) ≡ 𝟙 𝔻 ])
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[(F ∘f identity) .isFunctor .ident ≡ F .isFunctor .ident ]
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eqD-r : PathP
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(λ i →
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{A B C : Object ℂ} {f : ℂ [ A , B ]} {g : ℂ [ B , C ]} →
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eq→ i (ℂ [ g ∘ f ]) ≡ 𝔻 [ eq→ i g ∘ eq→ i f ])
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((F ∘f identity) .isFunctor .distrib) (F .isFunctor .distrib)
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ident-r : F ∘f identity ≡ F
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ident-r = Functor≡ eq* eq→ (IsFunctor≡ eqI-r eqD-r)
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module _ where
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private
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postulate
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eq* : (identity ∘f F) .func* ≡ F .func*
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eq→ : PathP
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(λ i → {x y : Object ℂ} → ℂ [ x , y ] → 𝔻 [ eq* i x , eq* i y ])
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((identity ∘f F) .func→) (F .func→)
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eqI : (λ i → ∀ {A : Object ℂ} → eq→ i (𝟙 ℂ {A}) ≡ 𝟙 𝔻 {eq* i A})
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[ ((identity ∘f F) .isFunctor .ident) ≡ (F .isFunctor .ident) ]
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eqD : PathP (λ i → {A B C : Object ℂ} {f : ℂ [ A , B ]} {g : ℂ [ B , C ]}
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→ eq→ i (ℂ [ g ∘ f ]) ≡ 𝔻 [ eq→ i g ∘ eq→ i f ])
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((identity ∘f F) .isFunctor .distrib) (F .isFunctor .distrib)
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-- (λ z → eq* i z) (eq→ i)
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ident-l : identity ∘f F ≡ F
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ident-l = Functor≡ eq* eq→ λ i → record { ident = eqI i ; distrib = eqD i }
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ident-r : F ∘f identity ≡ F
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ident-r = Functor≡ refl refl
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RawCat : RawCategory (lsuc (ℓ ⊔ ℓ')) (ℓ ⊔ ℓ')
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RawCat =
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record
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{ Object = Category ℓ ℓ'
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; Arrow = Functor
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; 𝟙 = identity
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; _∘_ = _∘f_
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-- What gives here? Why can I not name the variables directly?
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-- ; isCategory = record
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-- { assoc = λ {_ _ _ _ F G H} → assc {F = F} {G = G} {H = H}
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-- ; ident = ident-r , ident-l
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-- }
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}
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open IsCategory
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instance
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:isCategory: : IsCategory RawCat
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assoc :isCategory: {f = F} {G} {H} = assc {F = F} {G = G} {H = H}
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ident :isCategory: = ident-r , ident-l
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arrow-is-set :isCategory: = {!!}
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univalent :isCategory: = {!!}
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ident-l : identity ∘f F ≡ F
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ident-l = Functor≡ refl refl
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Cat : Category (lsuc (ℓ ⊔ ℓ')) (ℓ ⊔ ℓ')
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raw Cat = RawCat
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RawCat : RawCategory (lsuc (ℓ ⊔ ℓ')) (ℓ ⊔ ℓ')
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RawCat =
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record
|
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{ Object = Category ℓ ℓ'
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; Arrow = Functor
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; 𝟙 = identity
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; _∘_ = _∘f_
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||||
}
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private
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open RawCategory RawCat
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isAssociative : IsAssociative
|
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isAssociative {f = F} {G} {H} = assc {F = F} {G = G} {H = H}
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-- TODO: Rename `ident'` to `ident` after changing how names are exposed in Functor.
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ident' : IsIdentity identity
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ident' = ident-r , ident-l
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-- NB! `ArrowsAreSets RawCat` is *not* provable. The type of functors,
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-- however, form a groupoid! Therefore there is no (1-)category of
|
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-- categories. There does, however, exist a 2-category of 1-categories.
|
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|
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module _ {ℓ ℓ' : Level} where
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-- Because of the note above there is not category of categories.
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Cat : (unprovable : IsCategory RawCat) → Category (lsuc (ℓ ⊔ ℓ')) (ℓ ⊔ ℓ')
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Category.raw (Cat _) = RawCat
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Category.isCategory (Cat unprovable) = unprovable
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-- Category.raw Cat _ = RawCat
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-- Category.isCategory Cat unprovable = unprovable
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|
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-- The following to some extend depends on the category of categories being a
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-- category. In some places it may not actually be needed, however.
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module _ {ℓ ℓ' : Level} (unprovable : IsCategory (RawCat ℓ ℓ')) where
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module _ (ℂ 𝔻 : Category ℓ ℓ') where
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private
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Catt = Cat ℓ ℓ'
|
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Catt = Cat ℓ ℓ' unprovable
|
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:Object: = Object ℂ × Object 𝔻
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:Arrow: : :Object: → :Object: → Set ℓ'
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:Arrow: (c , d) (c' , d') = Arrow ℂ c c' × Arrow 𝔻 d d'
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:Arrow: (c , d) (c' , d') = ℂ [ c , c' ] × 𝔻 [ d , d' ]
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:𝟙: : {o : :Object:} → :Arrow: o o
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:𝟙: = 𝟙 ℂ , 𝟙 𝔻
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_:⊕:_ :
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|
@ -131,70 +82,67 @@ module _ {ℓ ℓ' : Level} where
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RawCategory.Arrow :rawProduct: = :Arrow:
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RawCategory.𝟙 :rawProduct: = :𝟙:
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RawCategory._∘_ :rawProduct: = _:⊕:_
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open RawCategory :rawProduct:
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module C = IsCategory (ℂ .isCategory)
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module D = IsCategory (𝔻 .isCategory)
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postulate
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issSet : {A B : RawCategory.Object :rawProduct:} → isSet (RawCategory.Arrow :rawProduct: A B)
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module C = Category ℂ
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module D = Category 𝔻
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open import Cubical.Sigma
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issSet : {A B : RawCategory.Object :rawProduct:} → isSet (Arrow A B)
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issSet = setSig {sA = C.arrowsAreSets} {sB = λ x → D.arrowsAreSets}
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ident' : IsIdentity :𝟙:
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ident'
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= Σ≡ (fst C.isIdentity) (fst D.isIdentity)
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, Σ≡ (snd C.isIdentity) (snd D.isIdentity)
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postulate univalent : Univalence.Univalent :rawProduct: ident'
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instance
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:isCategory: : IsCategory :rawProduct:
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-- :isCategory: = record
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-- { assoc = Σ≡ C.assoc D.assoc
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-- ; ident
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-- = Σ≡ (fst C.ident) (fst D.ident)
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-- , Σ≡ (snd C.ident) (snd D.ident)
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-- ; arrow-is-set = issSet
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-- ; univalent = {!!}
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-- }
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IsCategory.assoc :isCategory: = Σ≡ C.assoc D.assoc
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IsCategory.ident :isCategory:
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= Σ≡ (fst C.ident) (fst D.ident)
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, Σ≡ (snd C.ident) (snd D.ident)
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IsCategory.arrow-is-set :isCategory: = issSet
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IsCategory.univalent :isCategory: = {!!}
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IsCategory.isAssociative :isCategory: = Σ≡ C.isAssociative D.isAssociative
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IsCategory.isIdentity :isCategory: = ident'
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IsCategory.arrowsAreSets :isCategory: = issSet
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IsCategory.univalent :isCategory: = univalent
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:product: : Category ℓ ℓ'
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raw :product: = :rawProduct:
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Category.raw :product: = :rawProduct:
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proj₁ : Catt [ :product: , ℂ ]
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proj₁ = record { func* = fst ; func→ = fst ; isFunctor = record { ident = refl ; distrib = refl } }
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proj₁ = record
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{ raw = record { func* = fst ; func→ = fst }
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; isFunctor = record { isIdentity = refl ; isDistributive = refl }
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}
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proj₂ : Catt [ :product: , 𝔻 ]
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proj₂ = record { func* = snd ; func→ = snd ; isFunctor = record { ident = refl ; distrib = refl } }
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proj₂ = record
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{ raw = record { func* = snd ; func→ = snd }
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; isFunctor = record { isIdentity = refl ; isDistributive = refl }
|
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}
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module _ {X : Object Catt} (x₁ : Catt [ X , ℂ ]) (x₂ : Catt [ X , 𝔻 ]) where
|
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open Functor
|
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x : Functor X :product:
|
||||
x = record
|
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{ raw = record
|
||||
{ func* = λ x → x₁ .func* x , x₂ .func* x
|
||||
; func→ = λ x → func→ x₁ x , func→ x₂ x
|
||||
}
|
||||
; isFunctor = record
|
||||
{ isIdentity = Σ≡ x₁.isIdentity x₂.isIdentity
|
||||
; isDistributive = Σ≡ x₁.isDistributive x₂.isDistributive
|
||||
}
|
||||
}
|
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where
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open module x₁ = Functor x₁
|
||||
open module x₂ = Functor x₂
|
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|
||||
postulate x : Functor X :product:
|
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-- x = record
|
||||
-- { func* = λ x → x₁ .func* x , x₂ .func* x
|
||||
-- ; func→ = λ x → func→ x₁ x , func→ x₂ x
|
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-- ; isFunctor = record
|
||||
-- { ident = Σ≡ x₁.ident x₂.ident
|
||||
-- ; distrib = Σ≡ x₁.distrib x₂.distrib
|
||||
-- }
|
||||
-- }
|
||||
-- where
|
||||
-- open module x₁ = IsFunctor (x₁ .isFunctor)
|
||||
-- open module x₂ = IsFunctor (x₂ .isFunctor)
|
||||
isUniqL : Catt [ proj₁ ∘ x ] ≡ x₁
|
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isUniqL = Functor≡ eq* eq→
|
||||
where
|
||||
eq* : (Catt [ proj₁ ∘ x ]) .func* ≡ x₁ .func*
|
||||
eq* = refl
|
||||
eq→ : (λ i → {A : Object X} {B : Object X} → X [ A , B ] → ℂ [ eq* i A , eq* i B ])
|
||||
[ (Catt [ proj₁ ∘ x ]) .func→ ≡ x₁ .func→ ]
|
||||
eq→ = refl
|
||||
|
||||
-- Turned into postulate after:
|
||||
-- > commit e8215b2c051062c6301abc9b3f6ec67106259758 (HEAD -> dev, github/dev)
|
||||
-- > Author: Frederik Hanghøj Iversen <fhi.1990@gmail.com>
|
||||
-- > Date: Mon Feb 5 14:59:53 2018 +0100
|
||||
postulate isUniqL : Catt [ proj₁ ∘ x ] ≡ x₁
|
||||
-- isUniqL = Functor≡ eq* eq→ {!!}
|
||||
-- where
|
||||
-- eq* : (Catt [ proj₁ ∘ x ]) .func* ≡ x₁ .func*
|
||||
-- eq* = {!refl!}
|
||||
-- eq→ : (λ i → {A : Object X} {B : Object X} → X [ A , B ] → ℂ [ eq* i A , eq* i B ])
|
||||
-- [ (Catt [ proj₁ ∘ x ]) .func→ ≡ x₁ .func→ ]
|
||||
-- eq→ = refl
|
||||
-- postulate eqIsF : (Catt [ proj₁ ∘ x ]) .isFunctor ≡ x₁ .isFunctor
|
||||
-- eqIsF = IsFunctor≡ {!refl!} {!!}
|
||||
|
||||
postulate isUniqR : Catt [ proj₂ ∘ x ] ≡ x₂
|
||||
-- isUniqR = Functor≡ refl refl {!!} {!!}
|
||||
isUniqR : Catt [ proj₂ ∘ x ] ≡ x₂
|
||||
isUniqR = Functor≡ refl refl
|
||||
|
||||
isUniq : Catt [ proj₁ ∘ x ] ≡ x₁ × Catt [ proj₂ ∘ x ] ≡ x₂
|
||||
isUniq = isUniqL , isUniqR
|
||||
|
@ -203,36 +151,37 @@ module _ {ℓ ℓ' : Level} where
|
|||
uniq = x , isUniq
|
||||
|
||||
instance
|
||||
isProduct : IsProduct (Cat ℓ ℓ') proj₁ proj₂
|
||||
isProduct : IsProduct Catt proj₁ proj₂
|
||||
isProduct = uniq
|
||||
|
||||
product : Product {ℂ = (Cat ℓ ℓ')} ℂ 𝔻
|
||||
product : Product {ℂ = Catt} ℂ 𝔻
|
||||
product = record
|
||||
{ obj = :product:
|
||||
; proj₁ = proj₁
|
||||
; proj₂ = proj₂
|
||||
}
|
||||
|
||||
module _ {ℓ ℓ' : Level} where
|
||||
module _ {ℓ ℓ' : Level} (unprovable : IsCategory (RawCat ℓ ℓ')) where
|
||||
Catt = Cat ℓ ℓ' unprovable
|
||||
instance
|
||||
hasProducts : HasProducts (Cat ℓ ℓ')
|
||||
hasProducts = record { product = product }
|
||||
hasProducts : HasProducts Catt
|
||||
hasProducts = record { product = product unprovable }
|
||||
|
||||
-- Basically proves that `Cat ℓ ℓ` is cartesian closed.
|
||||
module _ (ℓ : Level) where
|
||||
module _ (ℓ : Level) (unprovable : IsCategory (RawCat ℓ ℓ)) where
|
||||
private
|
||||
open Data.Product
|
||||
open import Cat.Categories.Fun
|
||||
|
||||
Catℓ : Category (lsuc (ℓ ⊔ ℓ)) (ℓ ⊔ ℓ)
|
||||
Catℓ = Cat ℓ ℓ
|
||||
Catℓ = Cat ℓ ℓ unprovable
|
||||
module _ (ℂ 𝔻 : Category ℓ ℓ) where
|
||||
private
|
||||
:obj: : Object (Cat ℓ ℓ)
|
||||
:obj: : Object Catℓ
|
||||
:obj: = Fun {ℂ = ℂ} {𝔻 = 𝔻}
|
||||
|
||||
:func*: : Functor ℂ 𝔻 × Object ℂ → Object 𝔻
|
||||
:func*: (F , A) = F .func* A
|
||||
:func*: (F , A) = func* F A
|
||||
|
||||
module _ {dom cod : Functor ℂ 𝔻 × Object ℂ} where
|
||||
private
|
||||
|
@ -247,30 +196,30 @@ module _ (ℓ : Level) where
|
|||
B = proj₂ cod
|
||||
|
||||
:func→: : (pobj : NaturalTransformation F G × ℂ [ A , B ])
|
||||
→ 𝔻 [ F .func* A , G .func* B ]
|
||||
→ 𝔻 [ func* F A , func* G B ]
|
||||
:func→: ((θ , θNat) , f) = result
|
||||
where
|
||||
θA : 𝔻 [ F .func* A , G .func* A ]
|
||||
θA : 𝔻 [ func* F A , func* G A ]
|
||||
θA = θ A
|
||||
θB : 𝔻 [ F .func* B , G .func* B ]
|
||||
θB : 𝔻 [ func* F B , func* G B ]
|
||||
θB = θ B
|
||||
F→f : 𝔻 [ F .func* A , F .func* B ]
|
||||
F→f = F .func→ f
|
||||
G→f : 𝔻 [ G .func* A , G .func* B ]
|
||||
G→f = G .func→ f
|
||||
l : 𝔻 [ F .func* A , G .func* B ]
|
||||
F→f : 𝔻 [ func* F A , func* F B ]
|
||||
F→f = func→ F f
|
||||
G→f : 𝔻 [ func* G A , func* G B ]
|
||||
G→f = func→ G f
|
||||
l : 𝔻 [ func* F A , func* G B ]
|
||||
l = 𝔻 [ θB ∘ F→f ]
|
||||
r : 𝔻 [ F .func* A , G .func* B ]
|
||||
r : 𝔻 [ func* F A , func* G B ]
|
||||
r = 𝔻 [ G→f ∘ θA ]
|
||||
-- There are two choices at this point,
|
||||
-- but I suppose the whole point is that
|
||||
-- by `θNat f` we have `l ≡ r`
|
||||
-- lem : 𝔻 [ θ B ∘ F .func→ f ] ≡ 𝔻 [ G .func→ f ∘ θ A ]
|
||||
-- lem = θNat f
|
||||
result : 𝔻 [ F .func* A , G .func* B ]
|
||||
result : 𝔻 [ func* F A , func* G B ]
|
||||
result = l
|
||||
|
||||
_×p_ = product
|
||||
_×p_ = product unprovable
|
||||
|
||||
module _ {c : Functor ℂ 𝔻 × Object ℂ} where
|
||||
private
|
||||
|
@ -281,21 +230,21 @@ module _ (ℓ : Level) where
|
|||
|
||||
-- NaturalTransformation F G × ℂ .Arrow A B
|
||||
-- :ident: : :func→: {c} {c} (identityNat F , ℂ .𝟙) ≡ 𝔻 .𝟙
|
||||
-- :ident: = trans (proj₂ 𝔻.ident) (F .ident)
|
||||
-- :ident: = trans (proj₂ 𝔻.isIdentity) (F .isIdentity)
|
||||
-- where
|
||||
-- open module 𝔻 = IsCategory (𝔻 .isCategory)
|
||||
-- Unfortunately the equational version has some ambigous arguments.
|
||||
:ident: : :func→: {c} {c} (identityNat F , 𝟙 ℂ {o = proj₂ c}) ≡ 𝟙 𝔻
|
||||
:ident: : :func→: {c} {c} (identityNat F , 𝟙 ℂ {A = proj₂ c}) ≡ 𝟙 𝔻
|
||||
:ident: = begin
|
||||
:func→: {c} {c} (𝟙 (Product.obj (:obj: ×p ℂ)) {c}) ≡⟨⟩
|
||||
:func→: {c} {c} (identityNat F , 𝟙 ℂ) ≡⟨⟩
|
||||
𝔻 [ identityTrans F C ∘ F .func→ (𝟙 ℂ)] ≡⟨⟩
|
||||
𝔻 [ 𝟙 𝔻 ∘ F .func→ (𝟙 ℂ)] ≡⟨ proj₂ 𝔻.ident ⟩
|
||||
F .func→ (𝟙 ℂ) ≡⟨ F.ident ⟩
|
||||
𝔻 [ identityTrans F C ∘ func→ F (𝟙 ℂ)] ≡⟨⟩
|
||||
𝔻 [ 𝟙 𝔻 ∘ func→ F (𝟙 ℂ)] ≡⟨ proj₂ 𝔻.isIdentity ⟩
|
||||
func→ F (𝟙 ℂ) ≡⟨ F.isIdentity ⟩
|
||||
𝟙 𝔻 ∎
|
||||
where
|
||||
open module 𝔻 = IsCategory (𝔻 .isCategory)
|
||||
open module F = IsFunctor (F .isFunctor)
|
||||
open module 𝔻 = Category 𝔻
|
||||
open module F = Functor F
|
||||
|
||||
module _ {F×A G×B H×C : Functor ℂ 𝔻 × Object ℂ} where
|
||||
F = F×A .proj₁
|
||||
|
@ -330,48 +279,51 @@ module _ (ℓ : Level) where
|
|||
ηθ = proj₁ ηθNT
|
||||
ηθNat = proj₂ ηθNT
|
||||
|
||||
:distrib: :
|
||||
𝔻 [ 𝔻 [ η C ∘ θ C ] ∘ F .func→ ( ℂ [ g ∘ f ] ) ]
|
||||
≡ 𝔻 [ 𝔻 [ η C ∘ G .func→ g ] ∘ 𝔻 [ θ B ∘ F .func→ f ] ]
|
||||
:distrib: = begin
|
||||
𝔻 [ (ηθ C) ∘ F .func→ (ℂ [ g ∘ f ]) ]
|
||||
:isDistributive: :
|
||||
𝔻 [ 𝔻 [ η C ∘ θ C ] ∘ func→ F ( ℂ [ g ∘ f ] ) ]
|
||||
≡ 𝔻 [ 𝔻 [ η C ∘ func→ G g ] ∘ 𝔻 [ θ B ∘ func→ F f ] ]
|
||||
:isDistributive: = begin
|
||||
𝔻 [ (ηθ C) ∘ func→ F (ℂ [ g ∘ f ]) ]
|
||||
≡⟨ ηθNat (ℂ [ g ∘ f ]) ⟩
|
||||
𝔻 [ H .func→ (ℂ [ g ∘ f ]) ∘ (ηθ A) ]
|
||||
≡⟨ cong (λ φ → 𝔻 [ φ ∘ ηθ A ]) (H.distrib) ⟩
|
||||
𝔻 [ 𝔻 [ H .func→ g ∘ H .func→ f ] ∘ (ηθ A) ]
|
||||
≡⟨ sym assoc ⟩
|
||||
𝔻 [ H .func→ g ∘ 𝔻 [ H .func→ f ∘ ηθ A ] ]
|
||||
≡⟨ cong (λ φ → 𝔻 [ H .func→ g ∘ φ ]) assoc ⟩
|
||||
𝔻 [ H .func→ g ∘ 𝔻 [ 𝔻 [ H .func→ f ∘ η A ] ∘ θ A ] ]
|
||||
≡⟨ cong (λ φ → 𝔻 [ H .func→ g ∘ φ ]) (cong (λ φ → 𝔻 [ φ ∘ θ A ]) (sym (ηNat f))) ⟩
|
||||
𝔻 [ H .func→ g ∘ 𝔻 [ 𝔻 [ η B ∘ G .func→ f ] ∘ θ A ] ]
|
||||
≡⟨ cong (λ φ → 𝔻 [ H .func→ g ∘ φ ]) (sym assoc) ⟩
|
||||
𝔻 [ H .func→ g ∘ 𝔻 [ η B ∘ 𝔻 [ G .func→ f ∘ θ A ] ] ] ≡⟨ assoc ⟩
|
||||
𝔻 [ 𝔻 [ H .func→ g ∘ η B ] ∘ 𝔻 [ G .func→ f ∘ θ A ] ]
|
||||
≡⟨ cong (λ φ → 𝔻 [ φ ∘ 𝔻 [ G .func→ f ∘ θ A ] ]) (sym (ηNat g)) ⟩
|
||||
𝔻 [ 𝔻 [ η C ∘ G .func→ g ] ∘ 𝔻 [ G .func→ f ∘ θ A ] ]
|
||||
≡⟨ cong (λ φ → 𝔻 [ 𝔻 [ η C ∘ G .func→ g ] ∘ φ ]) (sym (θNat f)) ⟩
|
||||
𝔻 [ 𝔻 [ η C ∘ G .func→ g ] ∘ 𝔻 [ θ B ∘ F .func→ f ] ] ∎
|
||||
𝔻 [ func→ H (ℂ [ g ∘ f ]) ∘ (ηθ A) ]
|
||||
≡⟨ cong (λ φ → 𝔻 [ φ ∘ ηθ A ]) (H.isDistributive) ⟩
|
||||
𝔻 [ 𝔻 [ func→ H g ∘ func→ H f ] ∘ (ηθ A) ]
|
||||
≡⟨ sym isAssociative ⟩
|
||||
𝔻 [ func→ H g ∘ 𝔻 [ func→ H f ∘ ηθ A ] ]
|
||||
≡⟨ cong (λ φ → 𝔻 [ func→ H g ∘ φ ]) isAssociative ⟩
|
||||
𝔻 [ func→ H g ∘ 𝔻 [ 𝔻 [ func→ H f ∘ η A ] ∘ θ A ] ]
|
||||
≡⟨ cong (λ φ → 𝔻 [ func→ H g ∘ φ ]) (cong (λ φ → 𝔻 [ φ ∘ θ A ]) (sym (ηNat f))) ⟩
|
||||
𝔻 [ func→ H g ∘ 𝔻 [ 𝔻 [ η B ∘ func→ G f ] ∘ θ A ] ]
|
||||
≡⟨ cong (λ φ → 𝔻 [ func→ H g ∘ φ ]) (sym isAssociative) ⟩
|
||||
𝔻 [ func→ H g ∘ 𝔻 [ η B ∘ 𝔻 [ func→ G f ∘ θ A ] ] ]
|
||||
≡⟨ isAssociative ⟩
|
||||
𝔻 [ 𝔻 [ func→ H g ∘ η B ] ∘ 𝔻 [ func→ G f ∘ θ A ] ]
|
||||
≡⟨ cong (λ φ → 𝔻 [ φ ∘ 𝔻 [ func→ G f ∘ θ A ] ]) (sym (ηNat g)) ⟩
|
||||
𝔻 [ 𝔻 [ η C ∘ func→ G g ] ∘ 𝔻 [ func→ G f ∘ θ A ] ]
|
||||
≡⟨ cong (λ φ → 𝔻 [ 𝔻 [ η C ∘ func→ G g ] ∘ φ ]) (sym (θNat f)) ⟩
|
||||
𝔻 [ 𝔻 [ η C ∘ func→ G g ] ∘ 𝔻 [ θ B ∘ func→ F f ] ] ∎
|
||||
where
|
||||
open IsCategory (𝔻 .isCategory)
|
||||
open module H = IsFunctor (H .isFunctor)
|
||||
open Category 𝔻
|
||||
module H = Functor H
|
||||
|
||||
:eval: : Functor ((:obj: ×p ℂ) .Product.obj) 𝔻
|
||||
:eval: = record
|
||||
{ func* = :func*:
|
||||
; func→ = λ {dom} {cod} → :func→: {dom} {cod}
|
||||
{ raw = record
|
||||
{ func* = :func*:
|
||||
; func→ = λ {dom} {cod} → :func→: {dom} {cod}
|
||||
}
|
||||
; isFunctor = record
|
||||
{ ident = λ {o} → :ident: {o}
|
||||
; distrib = λ {f u n k y} → :distrib: {f} {u} {n} {k} {y}
|
||||
{ isIdentity = λ {o} → :ident: {o}
|
||||
; isDistributive = λ {f u n k y} → :isDistributive: {f} {u} {n} {k} {y}
|
||||
}
|
||||
}
|
||||
|
||||
module _ (𝔸 : Category ℓ ℓ) (F : Functor ((𝔸 ×p ℂ) .Product.obj) 𝔻) where
|
||||
open HasProducts (hasProducts {ℓ} {ℓ}) renaming (_|×|_ to parallelProduct)
|
||||
open HasProducts (hasProducts {ℓ} {ℓ} unprovable) renaming (_|×|_ to parallelProduct)
|
||||
|
||||
postulate
|
||||
transpose : Functor 𝔸 :obj:
|
||||
eq : Catℓ [ :eval: ∘ (parallelProduct transpose (𝟙 Catℓ {o = ℂ})) ] ≡ F
|
||||
eq : Catℓ [ :eval: ∘ (parallelProduct transpose (𝟙 Catℓ {A = ℂ})) ] ≡ F
|
||||
-- eq : Catℓ [ :eval: ∘ (HasProducts._|×|_ hasProducts transpose (𝟙 Catℓ {o = ℂ})) ] ≡ F
|
||||
-- eq' : (Catℓ [ :eval: ∘
|
||||
-- (record { product = product } HasProducts.|×| transpose)
|
||||
|
@ -384,10 +336,11 @@ module _ (ℓ : Level) where
|
|||
-- :eval: ∘ (parallelProduct F~ (𝟙 Catℓ {o = ℂ}))] ≡ F) catTranspose =
|
||||
-- transpose , eq
|
||||
|
||||
:isExponential: : IsExponential Catℓ ℂ 𝔻 :obj: :eval:
|
||||
:isExponential: = {!catTranspose!}
|
||||
where
|
||||
open HasProducts (hasProducts {ℓ} {ℓ}) using (_|×|_)
|
||||
postulate :isExponential: : IsExponential Catℓ ℂ 𝔻 :obj: :eval:
|
||||
-- :isExponential: : IsExponential Catℓ ℂ 𝔻 :obj: :eval:
|
||||
-- :isExponential: = {!catTranspose!}
|
||||
-- where
|
||||
-- open HasProducts (hasProducts {ℓ} {ℓ} unprovable) using (_|×|_)
|
||||
-- :isExponential: = λ 𝔸 F → transpose 𝔸 F , eq' 𝔸 F
|
||||
|
||||
-- :exponent: : Exponential (Cat ℓ ℓ) A B
|
||||
|
@ -398,5 +351,5 @@ module _ (ℓ : Level) where
|
|||
; isExponential = :isExponential:
|
||||
}
|
||||
|
||||
hasExponentials : HasExponentials (Cat ℓ ℓ)
|
||||
hasExponentials : HasExponentials Catℓ
|
||||
hasExponentials = record { exponent = :exponent: }
|
||||
|
|
|
@ -25,12 +25,12 @@ module _ (ℓa ℓb : Level) where
|
|||
c ⟨ g ∘ f ⟩ = _∘_ {c = c} g f
|
||||
|
||||
module _ {A B C D : Obj'} {f : Arr A B} {g : Arr B C} {h : Arr C D} where
|
||||
assoc : (D ⟨ h ∘ C ⟨ g ∘ f ⟩ ⟩) ≡ D ⟨ D ⟨ h ∘ g ⟩ ∘ f ⟩
|
||||
assoc = Σ≡ refl refl
|
||||
isAssociative : (D ⟨ h ∘ C ⟨ g ∘ f ⟩ ⟩) ≡ D ⟨ D ⟨ h ∘ g ⟩ ∘ f ⟩
|
||||
isAssociative = Σ≡ refl refl
|
||||
|
||||
module _ {A B : Obj'} {f : Arr A B} where
|
||||
ident : B ⟨ f ∘ one ⟩ ≡ f × B ⟨ one {B} ∘ f ⟩ ≡ f
|
||||
ident = (Σ≡ refl refl) , Σ≡ refl refl
|
||||
isIdentity : B ⟨ f ∘ one ⟩ ≡ f × B ⟨ one {B} ∘ f ⟩ ≡ f
|
||||
isIdentity = (Σ≡ refl refl) , Σ≡ refl refl
|
||||
|
||||
|
||||
RawFam : RawCategory (lsuc (ℓa ⊔ ℓb)) (ℓa ⊔ ℓb)
|
||||
|
@ -44,9 +44,9 @@ module _ (ℓa ℓb : Level) where
|
|||
instance
|
||||
isCategory : IsCategory RawFam
|
||||
isCategory = record
|
||||
{ assoc = λ {A} {B} {C} {D} {f} {g} {h} → assoc {D = D} {f} {g} {h}
|
||||
; ident = λ {A} {B} {f} → ident {A} {B} {f = f}
|
||||
; arrowIsSet = {!!}
|
||||
{ isAssociative = λ {A} {B} {C} {D} {f} {g} {h} → isAssociative {D = D} {f} {g} {h}
|
||||
; isIdentity = λ {A} {B} {f} → isIdentity {A} {B} {f = f}
|
||||
; arrowsAreSets = {!!}
|
||||
; univalent = {!!}
|
||||
}
|
||||
|
||||
|
|
|
@ -9,14 +9,6 @@ open import Cat.Category
|
|||
|
||||
open IsCategory
|
||||
|
||||
-- data Path {ℓ : Level} {A : Set ℓ} : (a b : A) → Set ℓ where
|
||||
-- emptyPath : {a : A} → Path a a
|
||||
-- concatenate : {a b c : A} → Path a b → Path b c → Path a b
|
||||
|
||||
-- import Data.List
|
||||
-- P : (a b : Object ℂ) → Set (ℓ ⊔ ℓ')
|
||||
-- P = {!Data.List.List ?!}
|
||||
-- Generalized paths:
|
||||
data Path {ℓ ℓ' : Level} {A : Set ℓ} (R : A → A → Set ℓ') : (a b : A) → Set (ℓ ⊔ ℓ') where
|
||||
empty : {a : A} → Path R a a
|
||||
cons : {a b c : A} → R b c → Path R a b → Path R a c
|
||||
|
@ -34,16 +26,16 @@ module _ {ℓ ℓ' : Level} (ℂ : Category ℓ ℓ') where
|
|||
open Category ℂ
|
||||
|
||||
private
|
||||
p-assoc : {A B C D : Object} {r : Path Arrow A B} {q : Path Arrow B C} {p : Path Arrow C D}
|
||||
p-isAssociative : {A B C D : Object} {r : Path Arrow A B} {q : Path Arrow B C} {p : Path Arrow C D}
|
||||
→ p ++ (q ++ r) ≡ (p ++ q) ++ r
|
||||
p-assoc {r = r} {q} {empty} = refl
|
||||
p-assoc {A} {B} {C} {D} {r = r} {q} {cons x p} = begin
|
||||
p-isAssociative {r = r} {q} {empty} = refl
|
||||
p-isAssociative {A} {B} {C} {D} {r = r} {q} {cons x p} = begin
|
||||
cons x p ++ (q ++ r) ≡⟨ cong (cons x) lem ⟩
|
||||
cons x ((p ++ q) ++ r) ≡⟨⟩
|
||||
(cons x p ++ q) ++ r ∎
|
||||
where
|
||||
lem : p ++ (q ++ r) ≡ ((p ++ q) ++ r)
|
||||
lem = p-assoc {r = r} {q} {p}
|
||||
lem = p-isAssociative {r = r} {q} {p}
|
||||
|
||||
ident-r : ∀ {A} {B} {p : Path Arrow A B} → concatenate p empty ≡ p
|
||||
ident-r {p = empty} = refl
|
||||
|
@ -65,8 +57,8 @@ module _ {ℓ ℓ' : Level} (ℂ : Category ℓ ℓ') where
|
|||
}
|
||||
RawIsCategoryFree : IsCategory RawFree
|
||||
RawIsCategoryFree = record
|
||||
{ assoc = λ { {f = f} {g} {h} → p-assoc {r = f} {g} {h}}
|
||||
; ident = ident-r , ident-l
|
||||
; arrowIsSet = {!!}
|
||||
{ isAssociative = λ { {f = f} {g} {h} → p-isAssociative {r = f} {g} {h}}
|
||||
; isIdentity = ident-r , ident-l
|
||||
; arrowsAreSets = {!!}
|
||||
; univalent = {!!}
|
||||
}
|
||||
|
|
|
@ -38,9 +38,6 @@ module _ {ℓc ℓc' ℓd ℓd' : Level} {ℂ : Category ℓc ℓc'} {𝔻 : Cat
|
|||
→ (f : ℂ [ A , B ])
|
||||
→ 𝔻 [ θ B ∘ F.func→ f ] ≡ 𝔻 [ G.func→ f ∘ θ A ]
|
||||
|
||||
-- naturalIsProp : ∀ θ → isProp (Natural θ)
|
||||
-- naturalIsProp θ x y = {!funExt!}
|
||||
|
||||
NaturalTransformation : Set (ℓc ⊔ ℓc' ⊔ ℓd')
|
||||
NaturalTransformation = Σ Transformation Natural
|
||||
|
||||
|
@ -63,8 +60,8 @@ module _ {ℓc ℓc' ℓd ℓd' : Level} {ℂ : Category ℓc ℓc'} {𝔻 : Cat
|
|||
identityNatural : (F : Functor ℂ 𝔻) → Natural F F (identityTrans F)
|
||||
identityNatural F {A = A} {B = B} f = begin
|
||||
𝔻 [ identityTrans F B ∘ F→ f ] ≡⟨⟩
|
||||
𝔻 [ 𝟙 𝔻 ∘ F→ f ] ≡⟨ proj₂ 𝔻.ident ⟩
|
||||
F→ f ≡⟨ sym (proj₁ 𝔻.ident) ⟩
|
||||
𝔻 [ 𝟙 𝔻 ∘ F→ f ] ≡⟨ proj₂ 𝔻.isIdentity ⟩
|
||||
F→ f ≡⟨ sym (proj₁ 𝔻.isIdentity) ⟩
|
||||
𝔻 [ F→ f ∘ 𝟙 𝔻 ] ≡⟨⟩
|
||||
𝔻 [ F→ f ∘ identityTrans F A ] ∎
|
||||
where
|
||||
|
@ -87,11 +84,11 @@ module _ {ℓc ℓc' ℓd ℓd' : Level} {ℂ : Category ℓc ℓc'} {𝔻 : Cat
|
|||
proj₁ ((θ , _) :⊕: (η , _)) = θ ∘nt η
|
||||
proj₂ ((θ , θNat) :⊕: (η , ηNat)) {A} {B} f = begin
|
||||
𝔻 [ (θ ∘nt η) B ∘ F.func→ f ] ≡⟨⟩
|
||||
𝔻 [ 𝔻 [ θ B ∘ η B ] ∘ F.func→ f ] ≡⟨ sym assoc ⟩
|
||||
𝔻 [ 𝔻 [ θ B ∘ η B ] ∘ F.func→ f ] ≡⟨ sym isAssociative ⟩
|
||||
𝔻 [ θ B ∘ 𝔻 [ η B ∘ F.func→ f ] ] ≡⟨ cong (λ φ → 𝔻 [ θ B ∘ φ ]) (ηNat f) ⟩
|
||||
𝔻 [ θ B ∘ 𝔻 [ G.func→ f ∘ η A ] ] ≡⟨ assoc ⟩
|
||||
𝔻 [ θ B ∘ 𝔻 [ G.func→ f ∘ η A ] ] ≡⟨ isAssociative ⟩
|
||||
𝔻 [ 𝔻 [ θ B ∘ G.func→ f ] ∘ η A ] ≡⟨ cong (λ φ → 𝔻 [ φ ∘ η A ]) (θNat f) ⟩
|
||||
𝔻 [ 𝔻 [ H.func→ f ∘ θ A ] ∘ η A ] ≡⟨ sym assoc ⟩
|
||||
𝔻 [ 𝔻 [ H.func→ f ∘ θ A ] ∘ η A ] ≡⟨ sym isAssociative ⟩
|
||||
𝔻 [ H.func→ f ∘ 𝔻 [ θ A ∘ η A ] ] ≡⟨⟩
|
||||
𝔻 [ H.func→ f ∘ (θ ∘nt η) A ] ∎
|
||||
where
|
||||
|
@ -100,59 +97,56 @@ module _ {ℓc ℓc' ℓd ℓd' : Level} {ℂ : Category ℓc ℓc'} {𝔻 : Cat
|
|||
NatComp = _:⊕:_
|
||||
|
||||
private
|
||||
module _ {F G : Functor ℂ 𝔻} where
|
||||
module 𝔻 = Category 𝔻
|
||||
module 𝔻 = Category 𝔻
|
||||
|
||||
transformationIsSet : isSet (Transformation F G)
|
||||
transformationIsSet _ _ p q i j C = 𝔻.arrowIsSet _ _ (λ l → p l C) (λ l → q l C) i j
|
||||
IsSet' : {ℓ : Level} (A : Set ℓ) → Set ℓ
|
||||
IsSet' A = {x y : A} → (p q : (λ _ → A) [ x ≡ y ]) → p ≡ q
|
||||
module _ {F G : Functor ℂ 𝔻} where
|
||||
transformationIsSet : isSet (Transformation F G)
|
||||
transformationIsSet _ _ p q i j C = 𝔻.arrowsAreSets _ _ (λ l → p l C) (λ l → q l C) i j
|
||||
|
||||
naturalIsProp : (θ : Transformation F G) → isProp (Natural F G θ)
|
||||
naturalIsProp θ θNat θNat' = lem
|
||||
where
|
||||
lem : (λ _ → Natural F G θ) [ (λ f → θNat f) ≡ (λ f → θNat' f) ]
|
||||
lem = λ i f → 𝔻.arrowIsSet _ _ (θNat f) (θNat' f) i
|
||||
naturalIsProp : (θ : Transformation F G) → isProp (Natural F G θ)
|
||||
naturalIsProp θ θNat θNat' = lem
|
||||
where
|
||||
lem : (λ _ → Natural F G θ) [ (λ f → θNat f) ≡ (λ f → θNat' f) ]
|
||||
lem = λ i f → 𝔻.arrowsAreSets _ _ (θNat f) (θNat' f) i
|
||||
|
||||
naturalTransformationIsSets : isSet (NaturalTransformation F G)
|
||||
naturalTransformationIsSets = sigPresSet transformationIsSet
|
||||
λ θ → ntypeCommulative
|
||||
(s≤s {n = Nat.suc Nat.zero} z≤n)
|
||||
(naturalIsProp θ)
|
||||
naturalTransformationIsSets : isSet (NaturalTransformation F G)
|
||||
naturalTransformationIsSets = sigPresSet transformationIsSet
|
||||
λ θ → ntypeCommulative
|
||||
(s≤s {n = Nat.suc Nat.zero} z≤n)
|
||||
(naturalIsProp θ)
|
||||
|
||||
module _ {A B C D : Functor ℂ 𝔻} {θ' : NaturalTransformation A B}
|
||||
{η' : NaturalTransformation B C} {ζ' : NaturalTransformation C D} where
|
||||
private
|
||||
θ = proj₁ θ'
|
||||
η = proj₁ η'
|
||||
ζ = proj₁ ζ'
|
||||
θNat = proj₂ θ'
|
||||
ηNat = proj₂ η'
|
||||
ζNat = proj₂ ζ'
|
||||
L : NaturalTransformation A D
|
||||
L = (_:⊕:_ {A} {C} {D} ζ' (_:⊕:_ {A} {B} {C} η' θ'))
|
||||
R : NaturalTransformation A D
|
||||
R = (_:⊕:_ {A} {B} {D} (_:⊕:_ {B} {C} {D} ζ' η') θ')
|
||||
_g⊕f_ = _:⊕:_ {A} {B} {C}
|
||||
_h⊕g_ = _:⊕:_ {B} {C} {D}
|
||||
:assoc: : L ≡ R
|
||||
:assoc: = lemSig (naturalIsProp {F = A} {D})
|
||||
L R (funExt (λ x → assoc))
|
||||
where
|
||||
open Category 𝔻
|
||||
module _ {A B C D : Functor ℂ 𝔻} {θ' : NaturalTransformation A B}
|
||||
{η' : NaturalTransformation B C} {ζ' : NaturalTransformation C D} where
|
||||
private
|
||||
θ = proj₁ θ'
|
||||
η = proj₁ η'
|
||||
ζ = proj₁ ζ'
|
||||
θNat = proj₂ θ'
|
||||
ηNat = proj₂ η'
|
||||
ζNat = proj₂ ζ'
|
||||
L : NaturalTransformation A D
|
||||
L = (_:⊕:_ {A} {C} {D} ζ' (_:⊕:_ {A} {B} {C} η' θ'))
|
||||
R : NaturalTransformation A D
|
||||
R = (_:⊕:_ {A} {B} {D} (_:⊕:_ {B} {C} {D} ζ' η') θ')
|
||||
_g⊕f_ = _:⊕:_ {A} {B} {C}
|
||||
_h⊕g_ = _:⊕:_ {B} {C} {D}
|
||||
:isAssociative: : L ≡ R
|
||||
:isAssociative: = lemSig (naturalIsProp {F = A} {D})
|
||||
L R (funExt (λ x → isAssociative))
|
||||
where
|
||||
open Category 𝔻
|
||||
|
||||
private
|
||||
module _ {A B : Functor ℂ 𝔻} {f : NaturalTransformation A B} where
|
||||
private
|
||||
allNatural = naturalIsProp {F = A} {B}
|
||||
f' = proj₁ f
|
||||
module 𝔻Data = Category 𝔻
|
||||
eq-r : ∀ C → (𝔻 [ f' C ∘ identityTrans A C ]) ≡ f' C
|
||||
eq-r C = begin
|
||||
𝔻 [ f' C ∘ identityTrans A C ] ≡⟨⟩
|
||||
𝔻 [ f' C ∘ 𝔻Data.𝟙 ] ≡⟨ proj₁ (𝔻.ident {A} {B}) ⟩
|
||||
f' C ∎
|
||||
eq-l : ∀ C → (𝔻 [ identityTrans B C ∘ f' C ]) ≡ f' C
|
||||
eq-l C = proj₂ (𝔻.ident {A} {B})
|
||||
allNatural = naturalIsProp {F = A} {B}
|
||||
f' = proj₁ f
|
||||
eq-r : ∀ C → (𝔻 [ f' C ∘ identityTrans A C ]) ≡ f' C
|
||||
eq-r C = begin
|
||||
𝔻 [ f' C ∘ identityTrans A C ] ≡⟨⟩
|
||||
𝔻 [ f' C ∘ 𝔻.𝟙 ] ≡⟨ proj₁ 𝔻.isIdentity ⟩
|
||||
f' C ∎
|
||||
eq-l : ∀ C → (𝔻 [ identityTrans B C ∘ f' C ]) ≡ f' C
|
||||
eq-l C = proj₂ 𝔻.isIdentity
|
||||
ident-r : (_:⊕:_ {A} {A} {B} f (identityNat A)) ≡ f
|
||||
ident-r = lemSig allNatural _ _ (funExt eq-r)
|
||||
ident-l : (_:⊕:_ {A} {B} {B} (identityNat B) f) ≡ f
|
||||
|
@ -174,9 +168,9 @@ module _ {ℓc ℓc' ℓd ℓd' : Level} {ℂ : Category ℓc ℓc'} {𝔻 : Cat
|
|||
instance
|
||||
:isCategory: : IsCategory RawFun
|
||||
:isCategory: = record
|
||||
{ assoc = λ {A B C D} → :assoc: {A} {B} {C} {D}
|
||||
; ident = λ {A B} → :ident: {A} {B}
|
||||
; arrowIsSet = λ {F} {G} → naturalTransformationIsSets {F} {G}
|
||||
{ isAssociative = λ {A B C D} → :isAssociative: {A} {B} {C} {D}
|
||||
; isIdentity = λ {A B} → :ident: {A} {B}
|
||||
; arrowsAreSets = λ {F} {G} → naturalTransformationIsSets {F} {G}
|
||||
; univalent = {!!}
|
||||
}
|
||||
|
||||
|
|
|
@ -149,10 +149,10 @@ module _ {A B C D : Set} {S : Subset (A × B)} {R : Subset (B × C)} {Q : Subset
|
|||
≃ (Σ[ b ∈ B ] (a , b) ∈ S × (Σ[ c ∈ C ] (b , c) ∈ R × (c , d) ∈ Q))
|
||||
equi = fwd Cubical.FromStdLib., isequiv
|
||||
|
||||
-- assocc : Q + (R + S) ≡ (Q + R) + S
|
||||
is-assoc : (Σ[ c ∈ C ] (Σ[ b ∈ B ] (a , b) ∈ S × (b , c) ∈ R) × (c , d) ∈ Q)
|
||||
-- isAssociativec : Q + (R + S) ≡ (Q + R) + S
|
||||
is-isAssociative : (Σ[ c ∈ C ] (Σ[ b ∈ B ] (a , b) ∈ S × (b , c) ∈ R) × (c , d) ∈ Q)
|
||||
≡ (Σ[ b ∈ B ] (a , b) ∈ S × (Σ[ c ∈ C ] (b , c) ∈ R × (c , d) ∈ Q))
|
||||
is-assoc = equivToPath equi
|
||||
is-isAssociative = equivToPath equi
|
||||
|
||||
RawRel : RawCategory (lsuc lzero) (lsuc lzero)
|
||||
RawRel = record
|
||||
|
@ -164,8 +164,8 @@ RawRel = record
|
|||
|
||||
RawIsCategoryRel : IsCategory RawRel
|
||||
RawIsCategoryRel = record
|
||||
{ assoc = funExt is-assoc
|
||||
; ident = funExt ident-l , funExt ident-r
|
||||
; arrowIsSet = {!!}
|
||||
{ isAssociative = funExt is-isAssociative
|
||||
; isIdentity = funExt ident-l , funExt ident-r
|
||||
; arrowsAreSets = {!!}
|
||||
; univalent = {!!}
|
||||
}
|
||||
|
|
|
@ -25,10 +25,10 @@ module _ (ℓ : Level) where
|
|||
_∘_ SetsRaw = Function._∘′_
|
||||
|
||||
SetsIsCategory : IsCategory SetsRaw
|
||||
assoc SetsIsCategory = refl
|
||||
proj₁ (ident SetsIsCategory) = funExt λ _ → refl
|
||||
proj₂ (ident SetsIsCategory) = funExt λ _ → refl
|
||||
arrowIsSet SetsIsCategory {B = (_ , s)} = setPi λ _ → s
|
||||
isAssociative SetsIsCategory = refl
|
||||
proj₁ (isIdentity SetsIsCategory) = funExt λ _ → refl
|
||||
proj₂ (isIdentity SetsIsCategory) = funExt λ _ → refl
|
||||
arrowsAreSets SetsIsCategory {B = (_ , s)} = setPi λ _ → s
|
||||
univalent SetsIsCategory = {!!}
|
||||
|
||||
𝓢𝓮𝓽 Sets : Category (lsuc ℓ) ℓ
|
||||
|
@ -94,12 +94,12 @@ module _ {ℓa ℓb : Level} where
|
|||
representable : {ℂ : Category ℓa ℓb} → Category.Object ℂ → Representable ℂ
|
||||
representable {ℂ = ℂ} A = record
|
||||
{ raw = record
|
||||
{ func* = λ B → ℂ [ A , B ] , arrowIsSet
|
||||
{ func* = λ B → ℂ [ A , B ] , arrowsAreSets
|
||||
; func→ = ℂ [_∘_]
|
||||
}
|
||||
; isFunctor = record
|
||||
{ ident = funExt λ _ → proj₂ ident
|
||||
; distrib = funExt λ x → sym assoc
|
||||
{ isIdentity = funExt λ _ → proj₂ isIdentity
|
||||
; isDistributive = funExt λ x → sym isAssociative
|
||||
}
|
||||
}
|
||||
where
|
||||
|
@ -109,12 +109,12 @@ module _ {ℓa ℓb : Level} where
|
|||
presheaf : {ℂ : Category ℓa ℓb} → Category.Object (Opposite ℂ) → Presheaf ℂ
|
||||
presheaf {ℂ = ℂ} B = record
|
||||
{ raw = record
|
||||
{ func* = λ A → ℂ [ A , B ] , arrowIsSet
|
||||
{ func* = λ A → ℂ [ A , B ] , arrowsAreSets
|
||||
; func→ = λ f g → ℂ [ g ∘ f ]
|
||||
}
|
||||
; isFunctor = record
|
||||
{ ident = funExt λ x → proj₁ ident
|
||||
; distrib = funExt λ x → assoc
|
||||
{ isIdentity = funExt λ x → proj₁ isIdentity
|
||||
; isDistributive = funExt λ x → isAssociative
|
||||
}
|
||||
}
|
||||
where
|
||||
|
|
|
@ -49,6 +49,9 @@ record RawCategory (ℓa ℓb : Level) : Set (lsuc (ℓa ⊔ ℓb)) where
|
|||
IsIdentity id = {A B : Object} {f : Arrow A B}
|
||||
→ f ∘ id ≡ f × id ∘ f ≡ f
|
||||
|
||||
ArrowsAreSets : Set (ℓa ⊔ ℓb)
|
||||
ArrowsAreSets = ∀ {A B : Object} → isSet (Arrow A B)
|
||||
|
||||
IsInverseOf : ∀ {A B} → (Arrow A B) → (Arrow B A) → Set ℓb
|
||||
IsInverseOf = λ f g → g ∘ f ≡ 𝟙 × f ∘ g ≡ 𝟙
|
||||
|
||||
|
@ -80,9 +83,9 @@ record RawCategory (ℓa ℓb : Level) : Set (lsuc (ℓa ⊔ ℓb)) where
|
|||
-- Univalence is indexed by a raw category as well as an identity proof.
|
||||
module Univalence {ℓa ℓb : Level} (ℂ : RawCategory ℓa ℓb) where
|
||||
open RawCategory ℂ
|
||||
module _ (ident : IsIdentity 𝟙) where
|
||||
module _ (isIdentity : IsIdentity 𝟙) where
|
||||
idIso : (A : Object) → A ≅ A
|
||||
idIso A = 𝟙 , (𝟙 , ident)
|
||||
idIso A = 𝟙 , (𝟙 , isIdentity)
|
||||
|
||||
-- Lemma 9.1.4 in [HoTT]
|
||||
id-to-iso : (A B : Object) → A ≡ B → A ≅ B
|
||||
|
@ -98,10 +101,10 @@ record IsCategory {ℓa ℓb : Level} (ℂ : RawCategory ℓa ℓb) : Set (lsuc
|
|||
open RawCategory ℂ
|
||||
open Univalence ℂ public
|
||||
field
|
||||
assoc : IsAssociative
|
||||
ident : IsIdentity 𝟙
|
||||
arrowIsSet : ∀ {A B : Object} → isSet (Arrow A B)
|
||||
univalent : Univalent ident
|
||||
isAssociative : IsAssociative
|
||||
isIdentity : IsIdentity 𝟙
|
||||
arrowsAreSets : ArrowsAreSets
|
||||
univalent : Univalent isIdentity
|
||||
|
||||
-- `IsCategory` is a mere proposition.
|
||||
module _ {ℓa ℓb : Level} {C : RawCategory ℓa ℓb} where
|
||||
|
@ -112,12 +115,12 @@ module _ {ℓa ℓb : Level} {C : RawCategory ℓa ℓb} where
|
|||
open import Cubical.NType.Properties
|
||||
|
||||
propIsAssociative : isProp IsAssociative
|
||||
propIsAssociative x y i = arrowIsSet _ _ x y i
|
||||
propIsAssociative x y i = arrowsAreSets _ _ x y i
|
||||
|
||||
propIsIdentity : ∀ {f : ∀ {A} → Arrow A A} → isProp (IsIdentity f)
|
||||
propIsIdentity a b i
|
||||
= arrowIsSet _ _ (fst a) (fst b) i
|
||||
, arrowIsSet _ _ (snd a) (snd b) i
|
||||
= arrowsAreSets _ _ (fst a) (fst b) i
|
||||
, arrowsAreSets _ _ (snd a) (snd b) i
|
||||
|
||||
propArrowIsSet : isProp (∀ {A B} → isSet (Arrow A B))
|
||||
propArrowIsSet a b i = isSetIsProp a b i
|
||||
|
@ -126,9 +129,9 @@ module _ {ℓa ℓb : Level} {C : RawCategory ℓa ℓb} where
|
|||
propIsInverseOf x y = λ i →
|
||||
let
|
||||
h : fst x ≡ fst y
|
||||
h = arrowIsSet _ _ (fst x) (fst y)
|
||||
h = arrowsAreSets _ _ (fst x) (fst y)
|
||||
hh : snd x ≡ snd y
|
||||
hh = arrowIsSet _ _ (snd x) (snd y)
|
||||
hh = arrowsAreSets _ _ (snd x) (snd y)
|
||||
in h i , hh i
|
||||
|
||||
module _ {A B : Object} {f : Arrow A B} where
|
||||
|
@ -139,14 +142,14 @@ module _ {ℓa ℓb : Level} {C : RawCategory ℓa ℓb} where
|
|||
open Cubical.NType.Properties
|
||||
geq : g ≡ g'
|
||||
geq = begin
|
||||
g ≡⟨ sym (fst ident) ⟩
|
||||
g ≡⟨ sym (fst isIdentity) ⟩
|
||||
g ∘ 𝟙 ≡⟨ cong (λ φ → g ∘ φ) (sym ε') ⟩
|
||||
g ∘ (f ∘ g') ≡⟨ assoc ⟩
|
||||
g ∘ (f ∘ g') ≡⟨ isAssociative ⟩
|
||||
(g ∘ f) ∘ g' ≡⟨ cong (λ φ → φ ∘ g') η ⟩
|
||||
𝟙 ∘ g' ≡⟨ snd ident ⟩
|
||||
𝟙 ∘ g' ≡⟨ snd isIdentity ⟩
|
||||
g' ∎
|
||||
|
||||
propUnivalent : isProp (Univalent ident)
|
||||
propUnivalent : isProp (Univalent isIdentity)
|
||||
propUnivalent a b i = propPi (λ iso → propHasLevel ⟨-2⟩) a b i
|
||||
|
||||
private
|
||||
|
@ -159,23 +162,28 @@ module _ {ℓa ℓb : Level} {C : RawCategory ℓa ℓb} where
|
|||
-- projections of `IsCategory` - I've arbitrarily chosed to use this
|
||||
-- result from `x : IsCategory C`. I don't know which (if any) possibly
|
||||
-- adverse effects this may have.
|
||||
ident : (λ _ → IsIdentity 𝟙) [ X.ident ≡ Y.ident ]
|
||||
ident = propIsIdentity x X.ident Y.ident
|
||||
isIdentity : (λ _ → IsIdentity 𝟙) [ X.isIdentity ≡ Y.isIdentity ]
|
||||
isIdentity = propIsIdentity x X.isIdentity Y.isIdentity
|
||||
done : x ≡ y
|
||||
U : ∀ {a : IsIdentity 𝟙} → (λ _ → IsIdentity 𝟙) [ X.ident ≡ a ] → (b : Univalent a) → Set _
|
||||
U eqwal bbb = (λ i → Univalent (eqwal i)) [ X.univalent ≡ bbb ]
|
||||
U : ∀ {a : IsIdentity 𝟙}
|
||||
→ (λ _ → IsIdentity 𝟙) [ X.isIdentity ≡ a ]
|
||||
→ (b : Univalent a)
|
||||
→ Set _
|
||||
U eqwal bbb =
|
||||
(λ i → Univalent (eqwal i))
|
||||
[ X.univalent ≡ bbb ]
|
||||
P : (y : IsIdentity 𝟙)
|
||||
→ (λ _ → IsIdentity 𝟙) [ X.ident ≡ y ] → Set _
|
||||
→ (λ _ → IsIdentity 𝟙) [ X.isIdentity ≡ y ] → Set _
|
||||
P y eq = ∀ (b' : Univalent y) → U eq b'
|
||||
helper : ∀ (b' : Univalent X.ident)
|
||||
→ (λ _ → Univalent X.ident) [ X.univalent ≡ b' ]
|
||||
helper : ∀ (b' : Univalent X.isIdentity)
|
||||
→ (λ _ → Univalent X.isIdentity) [ X.univalent ≡ b' ]
|
||||
helper univ = propUnivalent x X.univalent univ
|
||||
foo = pathJ P helper Y.ident ident
|
||||
eqUni : U ident Y.univalent
|
||||
foo = pathJ P helper Y.isIdentity isIdentity
|
||||
eqUni : U isIdentity Y.univalent
|
||||
eqUni = foo Y.univalent
|
||||
IC.assoc (done i) = propIsAssociative x X.assoc Y.assoc i
|
||||
IC.ident (done i) = ident i
|
||||
IC.arrowIsSet (done i) = propArrowIsSet x X.arrowIsSet Y.arrowIsSet i
|
||||
IC.isAssociative (done i) = propIsAssociative x X.isAssociative Y.isAssociative i
|
||||
IC.isIdentity (done i) = isIdentity i
|
||||
IC.arrowsAreSets (done i) = propArrowIsSet x X.arrowsAreSets Y.arrowsAreSets i
|
||||
IC.univalent (done i) = eqUni i
|
||||
|
||||
propIsCategory : isProp (IsCategory C)
|
||||
|
@ -208,9 +216,9 @@ module _ {ℓa ℓb : Level} (ℂ : Category ℓa ℓb) where
|
|||
RawCategory._∘_ OpRaw = Function.flip _∘_
|
||||
|
||||
OpIsCategory : IsCategory OpRaw
|
||||
IsCategory.assoc OpIsCategory = sym assoc
|
||||
IsCategory.ident OpIsCategory = swap ident
|
||||
IsCategory.arrowIsSet OpIsCategory = arrowIsSet
|
||||
IsCategory.isAssociative OpIsCategory = sym isAssociative
|
||||
IsCategory.isIdentity OpIsCategory = swap isIdentity
|
||||
IsCategory.arrowsAreSets OpIsCategory = arrowsAreSets
|
||||
IsCategory.univalent OpIsCategory = {!!}
|
||||
|
||||
Opposite : Category ℓa ℓb
|
||||
|
@ -234,9 +242,9 @@ module _ {ℓa ℓb : Level} {ℂ : Category ℓa ℓb} where
|
|||
open IsCategory
|
||||
module IsCat = IsCategory (ℂ .isCategory)
|
||||
rawIsCat : (i : I) → IsCategory (rawOp i)
|
||||
assoc (rawIsCat i) = IsCat.assoc
|
||||
ident (rawIsCat i) = IsCat.ident
|
||||
arrowIsSet (rawIsCat i) = IsCat.arrowIsSet
|
||||
isAssociative (rawIsCat i) = IsCat.isAssociative
|
||||
isIdentity (rawIsCat i) = IsCat.isIdentity
|
||||
arrowsAreSets (rawIsCat i) = IsCat.arrowsAreSets
|
||||
univalent (rawIsCat i) = IsCat.univalent
|
||||
|
||||
Opposite-is-involution : Opposite (Opposite ℂ) ≡ ℂ
|
||||
|
|
|
@ -35,5 +35,6 @@ module _ {ℓ ℓ'} (ℂ : Category ℓ ℓ') {{hasProducts : HasProducts ℂ}}
|
|||
transpose A f = proj₁ (isExponential A f)
|
||||
|
||||
record HasExponentials {ℓ ℓ' : Level} (ℂ : Category ℓ ℓ') {{_ : HasProducts ℂ}} : Set (ℓ ⊔ ℓ') where
|
||||
open Exponential public
|
||||
field
|
||||
exponent : (A B : Object ℂ) → Exponential ℂ A B
|
||||
|
|
|
@ -7,7 +7,7 @@ open import Function
|
|||
|
||||
open import Cat.Category
|
||||
|
||||
open Category hiding (_∘_ ; raw)
|
||||
open Category hiding (_∘_ ; raw ; IsIdentity)
|
||||
|
||||
module _ {ℓc ℓc' ℓd ℓd'}
|
||||
(ℂ : Category ℓc ℓc')
|
||||
|
@ -23,42 +23,40 @@ module _ {ℓc ℓc' ℓd ℓd'}
|
|||
func* : Object ℂ → Object 𝔻
|
||||
func→ : ∀ {A B} → ℂ [ A , B ] → 𝔻 [ func* A , func* B ]
|
||||
|
||||
IsIdentity : Set _
|
||||
IsIdentity = {A : Object ℂ} → func→ (𝟙 ℂ {A}) ≡ 𝟙 𝔻 {func* A}
|
||||
|
||||
IsDistributive : Set _
|
||||
IsDistributive = {A B C : Object ℂ} {f : ℂ [ A , B ]} {g : ℂ [ B , C ]}
|
||||
→ func→ (ℂ [ g ∘ f ]) ≡ 𝔻 [ func→ g ∘ func→ f ]
|
||||
|
||||
record IsFunctor (F : RawFunctor) : 𝓤 where
|
||||
open RawFunctor F
|
||||
open RawFunctor F public
|
||||
field
|
||||
ident : {c : Object ℂ} → func→ (𝟙 ℂ {c}) ≡ 𝟙 𝔻 {func* c}
|
||||
distrib : {A B C : Object ℂ} {f : ℂ [ A , B ]} {g : ℂ [ B , C ]}
|
||||
→ func→ (ℂ [ g ∘ f ]) ≡ 𝔻 [ func→ g ∘ func→ f ]
|
||||
isIdentity : IsIdentity
|
||||
isDistributive : IsDistributive
|
||||
|
||||
record Functor : Set (ℓc ⊔ ℓc' ⊔ ℓd ⊔ ℓd') where
|
||||
field
|
||||
raw : RawFunctor
|
||||
{{isFunctor}} : IsFunctor raw
|
||||
|
||||
private
|
||||
module R = RawFunctor raw
|
||||
open IsFunctor isFunctor public
|
||||
|
||||
func* : Object ℂ → Object 𝔻
|
||||
func* = R.func*
|
||||
|
||||
func→ : ∀ {A B} → ℂ [ A , B ] → 𝔻 [ func* A , func* B ]
|
||||
func→ = R.func→
|
||||
|
||||
open IsFunctor
|
||||
open Functor
|
||||
|
||||
module _
|
||||
{ℓa ℓb : Level}
|
||||
{ℂ 𝔻 : Category ℓa ℓb}
|
||||
{F : RawFunctor ℂ 𝔻}
|
||||
(F : RawFunctor ℂ 𝔻)
|
||||
where
|
||||
private
|
||||
module 𝔻 = IsCategory (isCategory 𝔻)
|
||||
|
||||
propIsFunctor : isProp (IsFunctor _ _ F)
|
||||
propIsFunctor isF0 isF1 i = record
|
||||
{ ident = 𝔻.arrowIsSet _ _ isF0.ident isF1.ident i
|
||||
; distrib = 𝔻.arrowIsSet _ _ isF0.distrib isF1.distrib i
|
||||
{ isIdentity = 𝔻.arrowsAreSets _ _ isF0.isIdentity isF1.isIdentity i
|
||||
; isDistributive = 𝔻.arrowsAreSets _ _ isF0.isDistributive isF1.isDistributive i
|
||||
}
|
||||
where
|
||||
module isF0 = IsFunctor isF0
|
||||
|
@ -77,7 +75,7 @@ module _
|
|||
|
||||
IsFunctorIsProp' : IsProp' λ i → IsFunctor _ _ (F i)
|
||||
IsFunctorIsProp' isF0 isF1 = lemPropF {B = IsFunctor ℂ 𝔻}
|
||||
(\ F → propIsFunctor {F = F}) (\ i → F i)
|
||||
(\ F → propIsFunctor F) (\ i → F i)
|
||||
where
|
||||
open import Cubical.NType.Properties using (lemPropF)
|
||||
|
||||
|
@ -108,8 +106,8 @@ module _ {ℓ ℓ' : Level} {A B C : Category ℓ ℓ'} (F : Functor B C) (G : F
|
|||
dist : (F→ ∘ G→) (A [ α1 ∘ α0 ]) ≡ C [ (F→ ∘ G→) α1 ∘ (F→ ∘ G→) α0 ]
|
||||
dist = begin
|
||||
(F→ ∘ G→) (A [ α1 ∘ α0 ]) ≡⟨ refl ⟩
|
||||
F→ (G→ (A [ α1 ∘ α0 ])) ≡⟨ cong F→ (G .isFunctor .distrib)⟩
|
||||
F→ (B [ G→ α1 ∘ G→ α0 ]) ≡⟨ F .isFunctor .distrib ⟩
|
||||
F→ (G→ (A [ α1 ∘ α0 ])) ≡⟨ cong F→ (isDistributive G) ⟩
|
||||
F→ (B [ G→ α1 ∘ G→ α0 ]) ≡⟨ isDistributive F ⟩
|
||||
C [ (F→ ∘ G→) α1 ∘ (F→ ∘ G→) α0 ] ∎
|
||||
|
||||
_∘fr_ : RawFunctor A C
|
||||
|
@ -118,12 +116,12 @@ module _ {ℓ ℓ' : Level} {A B C : Category ℓ ℓ'} (F : Functor B C) (G : F
|
|||
instance
|
||||
isFunctor' : IsFunctor A C _∘fr_
|
||||
isFunctor' = record
|
||||
{ ident = begin
|
||||
{ isIdentity = begin
|
||||
(F→ ∘ G→) (𝟙 A) ≡⟨ refl ⟩
|
||||
F→ (G→ (𝟙 A)) ≡⟨ cong F→ (G .isFunctor .ident)⟩
|
||||
F→ (𝟙 B) ≡⟨ F .isFunctor .ident ⟩
|
||||
F→ (G→ (𝟙 A)) ≡⟨ cong F→ (isIdentity G)⟩
|
||||
F→ (𝟙 B) ≡⟨ isIdentity F ⟩
|
||||
𝟙 C ∎
|
||||
; distrib = dist
|
||||
; isDistributive = dist
|
||||
}
|
||||
|
||||
_∘f_ : Functor A C
|
||||
|
@ -137,7 +135,7 @@ identity = record
|
|||
; func→ = λ x → x
|
||||
}
|
||||
; isFunctor = record
|
||||
{ ident = refl
|
||||
; distrib = refl
|
||||
{ isIdentity = refl
|
||||
; isDistributive = refl
|
||||
}
|
||||
}
|
||||
|
|
|
@ -17,106 +17,77 @@ module _ {ℓ ℓ' : Level} {ℂ : Category ℓ ℓ'} { A B : Category.Object
|
|||
|
||||
iso-is-epi : Isomorphism f → Epimorphism {X = X} f
|
||||
iso-is-epi (f- , left-inv , right-inv) g₀ g₁ eq = begin
|
||||
g₀ ≡⟨ sym (proj₁ ident) ⟩
|
||||
g₀ ≡⟨ sym (proj₁ isIdentity) ⟩
|
||||
g₀ ∘ 𝟙 ≡⟨ cong (_∘_ g₀) (sym right-inv) ⟩
|
||||
g₀ ∘ (f ∘ f-) ≡⟨ assoc ⟩
|
||||
g₀ ∘ (f ∘ f-) ≡⟨ isAssociative ⟩
|
||||
(g₀ ∘ f) ∘ f- ≡⟨ cong (λ φ → φ ∘ f-) eq ⟩
|
||||
(g₁ ∘ f) ∘ f- ≡⟨ sym assoc ⟩
|
||||
(g₁ ∘ f) ∘ f- ≡⟨ sym isAssociative ⟩
|
||||
g₁ ∘ (f ∘ f-) ≡⟨ cong (_∘_ g₁) right-inv ⟩
|
||||
g₁ ∘ 𝟙 ≡⟨ proj₁ ident ⟩
|
||||
g₁ ∘ 𝟙 ≡⟨ proj₁ isIdentity ⟩
|
||||
g₁ ∎
|
||||
|
||||
iso-is-mono : Isomorphism f → Monomorphism {X = X} f
|
||||
iso-is-mono (f- , (left-inv , right-inv)) g₀ g₁ eq =
|
||||
begin
|
||||
g₀ ≡⟨ sym (proj₂ ident) ⟩
|
||||
g₀ ≡⟨ sym (proj₂ isIdentity) ⟩
|
||||
𝟙 ∘ g₀ ≡⟨ cong (λ φ → φ ∘ g₀) (sym left-inv) ⟩
|
||||
(f- ∘ f) ∘ g₀ ≡⟨ sym assoc ⟩
|
||||
(f- ∘ f) ∘ g₀ ≡⟨ sym isAssociative ⟩
|
||||
f- ∘ (f ∘ g₀) ≡⟨ cong (_∘_ f-) eq ⟩
|
||||
f- ∘ (f ∘ g₁) ≡⟨ assoc ⟩
|
||||
f- ∘ (f ∘ g₁) ≡⟨ isAssociative ⟩
|
||||
(f- ∘ f) ∘ g₁ ≡⟨ cong (λ φ → φ ∘ g₁) left-inv ⟩
|
||||
𝟙 ∘ g₁ ≡⟨ proj₂ ident ⟩
|
||||
𝟙 ∘ g₁ ≡⟨ proj₂ isIdentity ⟩
|
||||
g₁ ∎
|
||||
|
||||
iso-is-epi-mono : Isomorphism f → Epimorphism {X = X} f × Monomorphism {X = X} f
|
||||
iso-is-epi-mono iso = iso-is-epi iso , iso-is-mono iso
|
||||
|
||||
{-
|
||||
epi-mono-is-not-iso : ∀ {ℓ ℓ'} → ¬ ((ℂ : Category {ℓ} {ℓ'}) {A B X : Object ℂ} (f : Arrow ℂ A B ) → Epimorphism {ℂ = ℂ} {X = X} f → Monomorphism {ℂ = ℂ} {X = X} f → Isomorphism {ℂ = ℂ} f)
|
||||
epi-mono-is-not-iso f =
|
||||
let k = f {!!} {!!} {!!} {!!}
|
||||
in {!!}
|
||||
-}
|
||||
-- TODO: We want to avoid defining the yoneda embedding going through the
|
||||
-- category of categories (since it doesn't exist).
|
||||
open import Cat.Categories.Cat using (RawCat)
|
||||
|
||||
open import Cat.Category
|
||||
open Category
|
||||
open Functor
|
||||
module _ {ℓ : Level} {ℂ : Category ℓ ℓ} (unprovable : IsCategory (RawCat ℓ ℓ)) where
|
||||
open import Cat.Categories.Fun
|
||||
open import Cat.Categories.Sets
|
||||
module Cat = Cat.Categories.Cat
|
||||
open import Cat.Category.Exponential
|
||||
open Functor
|
||||
𝓢 = Sets ℓ
|
||||
private
|
||||
Catℓ : Category _ _
|
||||
Catℓ = record { raw = RawCat ℓ ℓ ; isCategory = unprovable}
|
||||
prshf = presheaf {ℂ = ℂ}
|
||||
module ℂ = Category ℂ
|
||||
|
||||
-- module _ {ℓ : Level} {ℂ : Category ℓ ℓ}
|
||||
-- {isSObj : isSet (ℂ .Object)}
|
||||
-- {isz2 : ∀ {ℓ} → {A B : Set ℓ} → isSet (Sets [ A , B ])} where
|
||||
-- -- open import Cat.Categories.Cat using (Cat)
|
||||
-- open import Cat.Categories.Fun
|
||||
-- open import Cat.Categories.Sets
|
||||
-- -- module Cat = Cat.Categories.Cat
|
||||
-- open import Cat.Category.Exponential
|
||||
-- private
|
||||
-- Catℓ = Cat ℓ ℓ
|
||||
-- prshf = presheaf {ℂ = ℂ}
|
||||
-- module ℂ = IsCategory (ℂ .isCategory)
|
||||
_⇑_ : (A B : Category.Object Catℓ) → Category.Object Catℓ
|
||||
A ⇑ B = (exponent A B) .obj
|
||||
where
|
||||
open HasExponentials (Cat.hasExponentials ℓ unprovable)
|
||||
|
||||
-- -- Exp : Set (lsuc (lsuc ℓ))
|
||||
-- -- Exp = Exponential (Cat (lsuc ℓ) ℓ)
|
||||
-- -- Sets (Opposite ℂ)
|
||||
module _ {A B : ℂ.Object} (f : ℂ [ A , B ]) where
|
||||
:func→: : NaturalTransformation (prshf A) (prshf B)
|
||||
:func→: = (λ C x → ℂ [ f ∘ x ]) , λ f₁ → funExt λ _ → ℂ.isAssociative
|
||||
|
||||
-- _⇑_ : (A B : Catℓ .Object) → Catℓ .Object
|
||||
-- A ⇑ B = (exponent A B) .obj
|
||||
-- where
|
||||
-- open HasExponentials (Cat.hasExponentials ℓ)
|
||||
module _ {c : Category.Object ℂ} where
|
||||
eqTrans : (λ _ → Transformation (prshf c) (prshf c))
|
||||
[ (λ _ x → ℂ [ ℂ.𝟙 ∘ x ]) ≡ identityTrans (prshf c) ]
|
||||
eqTrans = funExt λ x → funExt λ x → ℂ.isIdentity .proj₂
|
||||
|
||||
-- module _ {A B : ℂ .Object} (f : ℂ .Arrow A B) where
|
||||
-- :func→: : NaturalTransformation (prshf A) (prshf B)
|
||||
-- :func→: = (λ C x → ℂ [ f ∘ x ]) , λ f₁ → funExt λ _ → ℂ.assoc
|
||||
open import Cubical.NType.Properties
|
||||
open import Cat.Categories.Fun
|
||||
:ident: : :func→: (ℂ.𝟙 {c}) ≡ Category.𝟙 Fun {A = prshf c}
|
||||
:ident: = lemSig (naturalIsProp {F = prshf c} {prshf c}) _ _ eq
|
||||
where
|
||||
eq : (λ C x → ℂ [ ℂ.𝟙 ∘ x ]) ≡ identityTrans (prshf c)
|
||||
eq = funExt λ A → funExt λ B → proj₂ ℂ.isIdentity
|
||||
|
||||
-- module _ {c : ℂ .Object} where
|
||||
-- eqTrans : (λ _ → Transformation (prshf c) (prshf c))
|
||||
-- [ (λ _ x → ℂ [ ℂ .𝟙 ∘ x ]) ≡ identityTrans (prshf c) ]
|
||||
-- eqTrans = funExt λ x → funExt λ x → ℂ.ident .proj₂
|
||||
|
||||
-- eqNat : (λ i → Natural (prshf c) (prshf c) (eqTrans i))
|
||||
-- [(λ _ → funExt (λ _ → ℂ.assoc)) ≡ identityNatural (prshf c)]
|
||||
-- eqNat = λ i {A} {B} f →
|
||||
-- let
|
||||
-- open IsCategory (Sets .isCategory)
|
||||
-- lemm : (Sets [ eqTrans i B ∘ prshf c .func→ f ]) ≡
|
||||
-- (Sets [ prshf c .func→ f ∘ eqTrans i A ])
|
||||
-- lemm = {!!}
|
||||
-- lem : (λ _ → Sets [ Functor.func* (prshf c) A , prshf c .func* B ])
|
||||
-- [ Sets [ eqTrans i B ∘ prshf c .func→ f ]
|
||||
-- ≡ Sets [ prshf c .func→ f ∘ eqTrans i A ] ]
|
||||
-- lem
|
||||
-- = isz2 _ _ lemm _ i
|
||||
-- -- (Sets [ eqTrans i B ∘ prshf c .func→ f ])
|
||||
-- -- (Sets [ prshf c .func→ f ∘ eqTrans i A ])
|
||||
-- -- lemm
|
||||
-- -- _ i
|
||||
-- in
|
||||
-- lem
|
||||
-- -- eqNat = λ {A} {B} i ℂ[B,A] i' ℂ[A,c] →
|
||||
-- -- let
|
||||
-- -- k : ℂ [ {!!} , {!!} ]
|
||||
-- -- k = ℂ[A,c]
|
||||
-- -- in {!ℂ [ ? ∘ ? ]!}
|
||||
|
||||
-- :ident: : (:func→: (ℂ .𝟙 {c})) ≡ (Fun .𝟙 {o = prshf c})
|
||||
-- :ident: = Σ≡ eqTrans eqNat
|
||||
|
||||
-- yoneda : Functor ℂ (Fun {ℂ = Opposite ℂ} {𝔻 = Sets {ℓ}})
|
||||
-- yoneda = record
|
||||
-- { func* = prshf
|
||||
-- ; func→ = :func→:
|
||||
-- ; isFunctor = record
|
||||
-- { ident = :ident:
|
||||
-- ; distrib = {!!}
|
||||
-- }
|
||||
-- }
|
||||
yoneda : Functor ℂ (Fun {ℂ = Opposite ℂ} {𝔻 = 𝓢})
|
||||
yoneda = record
|
||||
{ raw = record
|
||||
{ func* = prshf
|
||||
; func→ = :func→:
|
||||
}
|
||||
; isFunctor = record
|
||||
{ isIdentity = :ident:
|
||||
; isDistributive = {!!}
|
||||
}
|
||||
}
|
||||
|
|
|
@ -20,28 +20,3 @@ module Equality where
|
|||
Σ≡ : a ≡ b
|
||||
proj₁ (Σ≡ i) = proj₁≡ i
|
||||
proj₂ (Σ≡ i) = proj₂≡ i
|
||||
|
||||
-- Remark 2.7.1: This theorem:
|
||||
--
|
||||
-- (x , u) ≡ (x , v) → u ≡ v
|
||||
--
|
||||
-- does *not* hold! We can only conclude that there *exists* `p : x ≡ x`
|
||||
-- such that
|
||||
--
|
||||
-- p* u ≡ v
|
||||
-- thm : isSet A → (∀ {a} → isSet (B a)) → isSet (Σ A B)
|
||||
-- thm sA sB (x , y) (x' , y') p q = res
|
||||
-- where
|
||||
-- x≡x'0 : x ≡ x'
|
||||
-- x≡x'0 = λ i → proj₁ (p i)
|
||||
-- x≡x'1 : x ≡ x'
|
||||
-- x≡x'1 = λ i → proj₁ (q i)
|
||||
-- someP : x ≡ x'
|
||||
-- someP = {!!}
|
||||
-- tricky : {!y!} ≡ y'
|
||||
-- tricky = {!!}
|
||||
-- -- res' : (λ _ → Σ A B) [ (x , y) ≡ (x' , y') ]
|
||||
-- res' : ({!!} , {!!}) ≡ ({!!} , {!!})
|
||||
-- res' = {!!}
|
||||
-- res : p ≡ q
|
||||
-- res i = {!res'!}
|
||||
|
|
Loading…
Reference in a new issue