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Minimize dependency on category of categories

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Frederik Hanghøj Iversen 2018-03-05 10:35:33 +01:00
parent 8f8800cb67
commit 77006011d3
1 changed files with 13 additions and 12 deletions
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25
src/Cat/Categories/Cat.agda
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@ -65,7 +65,6 @@ module _ (ℓ ℓ' : Level) where
module _ {ℓ ℓ' : Level} (unprovable : IsCategory (RawCat ℓ ℓ')) where
module _ (ℂ 𝔻 : Category ℓ ℓ') where
private
Catt = Cat ℓ ℓ' unprovable
:Object: = Object ℂ × Object 𝔻
:Arrow: : :Object: → :Object: → Set ℓ'
:Arrow: (c , d) (c' , d') = ℂ [ c , c' ] × 𝔻 [ d , d' ]
@ -105,19 +104,19 @@ module _ {ℓ ℓ' : Level} (unprovable : IsCategory (RawCat ℓ ℓ')) where
:product: : Category ℓ ℓ'
Category.raw :product: = :rawProduct:
proj₁ : Catt [ :product: , ℂ ]
proj₁ : Functor :product: ℂ
proj₁ = record
{ raw = record { func* = fst ; func→ = fst }
; isFunctor = record { isIdentity = refl ; isDistributive = refl }
}
proj₂ : Catt [ :product: , 𝔻 ]
proj₂ : Functor :product: 𝔻
proj₂ = record
{ raw = record { func* = snd ; func→ = snd }
; isFunctor = record { isIdentity = refl ; isDistributive = refl }
}
module _ {X : Object Catt} (x₁ : Catt [ X , ℂ ]) (x₂ : Catt [ X , 𝔻 ]) where
module _ {X : Category ℓ ℓ'} (x₁ : Functor X ℂ) (x₂ : Functor X 𝔻) where
x : Functor X :product:
x = record
{ raw = record
@ -133,29 +132,31 @@ module _ {ℓ ℓ' : Level} (unprovable : IsCategory (RawCat ℓ ℓ')) where
open module x₁ = Functor x₁
open module x₂ = Functor x₂
isUniqL : Catt [ proj₁ ∘ x ] ≡ x₁
isUniqL : F[ proj₁ ∘ x ] ≡ x₁
isUniqL = Functor≡ eq* eq→
where
eq* : (Catt [ proj₁ ∘ x ]) .func* ≡ x₁ .func*
eq* : (F[ 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→ ]
[ (F[ proj₁ ∘ x ]) .func→ ≡ x₁ .func→ ]
eq→ = refl
isUniqR : Catt [ proj₂ ∘ x ] ≡ x₂
isUniqR : F[ proj₂ ∘ x ] ≡ x₂
isUniqR = Functor≡ refl refl
isUniq : Catt [ proj₁ ∘ x ] ≡ x₁ × Catt [ proj₂ ∘ x ] ≡ x₂
isUniq : F[ proj₁ ∘ x ] ≡ x₁ × F[ proj₂ ∘ x ] ≡ x₂
isUniq = isUniqL , isUniqR
uniq : ∃![ x ] (Catt [ proj₁ ∘ x ] ≡ x₁ × Catt [ proj₂ ∘ x ] ≡ x₂)
uniq : ∃![ x ] (F[ proj₁ ∘ x ] ≡ x₁ × F[ proj₂ ∘ x ] ≡ x₂)
uniq = x , isUniq
Catℓ = Cat ℓ ℓ' unprovable
instance
isProduct : IsProduct Catt proj₁ proj₂
isProduct : IsProduct Catℓ proj₁ proj₂
isProduct = uniq
product : Product {ℂ = Catt} ℂ 𝔻
product : Product {ℂ = Catℓ} ℂ 𝔻
product = record
{ obj = :product:
; proj₁ = proj₁