1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
|
{-# OPTIONS --without-K --safe #-}
open import Categories.Category.Monoidal.Bundle using (MonoidalCategory; SymmetricMonoidalCategory)
open import Categories.Functor.Monoidal.Symmetric using (module Lax)
open import Category.Cocomplete.Finitely.Bundle using (FinitelyCocompleteCategory)
open import Data.Product.Base using (_,_)
open Lax using (SymmetricMonoidalFunctor)
open FinitelyCocompleteCategory
using ()
renaming (symmetricMonoidalCategory to smc)
module Functor.Instance.Decorate
{o o′ ℓ ℓ′ e e′}
(𝒞 : FinitelyCocompleteCategory o ℓ e)
{𝒟 : SymmetricMonoidalCategory o′ ℓ′ e′}
(F : SymmetricMonoidalFunctor (smc 𝒞) 𝒟) where
import Categories.Category.Monoidal.Reasoning as ⊗-Reasoning
import Categories.Diagram.Pushout as DiagramPushout
import Categories.Morphism.Reasoning as ⇒-Reasoning
open import Categories.Category using (Category; _[_,_]; _[_≈_]; _[_∘_])
open import Categories.Category.Cocartesian using (module CocartesianMonoidal)
open import Categories.Category.Monoidal.Properties using (coherence-inv₃)
open import Categories.Category.Monoidal.Utilities using (module Shorthands)
open import Categories.Functor.Core using (Functor)
open import Categories.Functor.Properties using ([_]-resp-≅)
open import Function.Base using () renaming (id to idf)
open import Category.Instance.Cospans 𝒞 using (Cospan; Cospans; Same)
open import Category.Instance.DecoratedCospans 𝒞 F using (DecoratedCospans)
open import Functor.Instance.Cospan.Stack using (⊗)
open import Functor.Instance.DecoratedCospan.Stack using () renaming (⊗ to ⊗′)
module 𝒞 = FinitelyCocompleteCategory 𝒞
module 𝒟 = SymmetricMonoidalCategory 𝒟
module F = SymmetricMonoidalFunctor F
module Cospans = Category Cospans
module DecoratedCospans = Category DecoratedCospans
module mc𝒞 = CocartesianMonoidal 𝒞.U 𝒞.cocartesian
-- For every cospan there exists a free decorated cospan
-- i.e. the original cospan with the empty decoration
private
variable
A A′ B B′ C C′ D : 𝒞.Obj
f : Cospans [ A , B ]
g : Cospans [ C , D ]
decorate : Cospans [ A , B ] → DecoratedCospans [ A , B ]
decorate f = record
{ cospan = f
; decoration = F₁ ¡ ∘ ε
}
where
open 𝒞 using (¡)
open 𝒟 using (_∘_)
open F using (ε; F₁)
identity : DecoratedCospans [ decorate (Cospans.id {A}) ≈ DecoratedCospans.id ]
identity = record
{ cospans-≈ = Cospans.Equiv.refl
; same-deco = elimˡ F.identity
}
where
open ⇒-Reasoning 𝒟.U
homomorphism : DecoratedCospans [ decorate (Cospans [ g ∘ f ]) ≈ DecoratedCospans [ decorate g ∘ decorate f ] ]
homomorphism {B} {C} {g} {A} {f} = record
{ cospans-≈ = Cospans.Equiv.refl
; same-deco = same-deco
}
where
open Cospan f using (N; f₂)
open Cospan g using () renaming (N to M; f₁ to g₁)
open 𝒟 using (U; monoidal; _⊗₁_; unitorˡ-commute-from) renaming (module unitorˡ to λ-)
open 𝒞 using (¡; ⊥; ¡-unique; pushout) renaming ([_,_] to [_,_]′; _+₁_ to infixr 10 _+₁_ )
open Category U
open Equiv
open ⇒-Reasoning U
open ⊗-Reasoning monoidal
open F.⊗-homo using () renaming (η to φ; commute to φ-commute)
open F using (F₁; ε)
open Shorthands monoidal
open DiagramPushout 𝒞.U using (Pushout)
open Pushout (pushout f₂ g₁) using (i₁; i₂)
open mc𝒞 using (unitorˡ)
open unitorˡ using () renaming (to to λ⇐′)
same-deco : F₁ 𝒞.id ∘ F₁ ¡ ∘ F.ε ≈ F₁ [ i₁ , i₂ ]′ ∘ φ (N , M) ∘ (F₁ ¡ ∘ ε) ⊗₁ (F₁ ¡ ∘ ε) ∘ ρ⇐
same-deco = begin
F₁ 𝒞.id ∘ F₁ ¡ ∘ ε ≈⟨ elimˡ F.identity ⟩
F₁ ¡ ∘ ε ≈⟨ F.F-resp-≈ (¡-unique _) ⟩∘⟨refl ⟩
F₁ ([ i₁ , i₂ ]′ 𝒞.∘ ¡ +₁ ¡ 𝒞.∘ λ⇐′) ∘ ε ≈⟨ refl⟩∘⟨ introʳ λ-.isoʳ ⟩
F₁ ([ i₁ , i₂ ]′ 𝒞.∘ ¡ +₁ ¡ 𝒞.∘ λ⇐′) ∘ ε ∘ λ⇒ ∘ λ⇐ ≈⟨ refl⟩∘⟨ refl⟩∘⟨ refl⟩∘⟨ coherence-inv₃ monoidal ⟩
F₁ ([ i₁ , i₂ ]′ 𝒞.∘ ¡ +₁ ¡ 𝒞.∘ λ⇐′) ∘ ε ∘ λ⇒ ∘ ρ⇐ ≈⟨ refl⟩∘⟨ extendʳ unitorˡ-commute-from ⟨
F₁ ([ i₁ , i₂ ]′ 𝒞.∘ ¡ +₁ ¡ 𝒞.∘ λ⇐′) ∘ λ⇒ ∘ id ⊗₁ ε ∘ ρ⇐ ≈⟨ pushˡ F.homomorphism ⟩
F₁ [ i₁ , i₂ ]′ ∘ F₁ (¡ +₁ ¡ 𝒞.∘ λ⇐′) ∘ λ⇒ ∘ id ⊗₁ ε ∘ ρ⇐ ≈⟨ push-center (sym F.homomorphism) ⟩
F₁ [ i₁ , i₂ ]′ ∘ F₁ (¡ +₁ ¡) ∘ F₁ λ⇐′ ∘ λ⇒ ∘ id ⊗₁ ε ∘ ρ⇐ ≈⟨ refl⟩∘⟨ refl⟩∘⟨ extendʳ (switch-fromtoˡ ([ F.F ]-resp-≅ unitorˡ) F.unitaryˡ) ⟨
F₁ [ i₁ , i₂ ]′ ∘ F₁ (¡ +₁ ¡) ∘ φ (⊥ , ⊥) ∘ ε ⊗₁ id ∘ id ⊗₁ ε ∘ ρ⇐ ≈⟨ refl⟩∘⟨ refl⟩∘⟨ refl⟩∘⟨ pullˡ (sym serialize₁₂) ⟩
F₁ [ i₁ , i₂ ]′ ∘ F₁ (¡ +₁ ¡) ∘ φ (⊥ , ⊥) ∘ ε ⊗₁ ε ∘ ρ⇐ ≈⟨ refl⟩∘⟨ extendʳ (φ-commute (¡ , ¡)) ⟨
F₁ [ i₁ , i₂ ]′ ∘ φ (N , M) ∘ F₁ ¡ ⊗₁ F₁ ¡ ∘ ε ⊗₁ ε ∘ ρ⇐ ≈⟨ refl⟩∘⟨ refl⟩∘⟨ pullˡ (sym ⊗-distrib-over-∘) ⟩
F₁ [ i₁ , i₂ ]′ ∘ φ (N , M) ∘ (F₁ ¡ ∘ ε) ⊗₁ (F₁ ¡ ∘ ε) ∘ ρ⇐ ∎
F-resp-≈ : Cospans [ f ≈ g ] → DecoratedCospans [ decorate f ≈ decorate g ]
F-resp-≈ f≈g = record
{ cospans-≈ = f≈g
; same-deco = pullˡ (sym F.homomorphism) ○ sym (F.F-resp-≈ (¡-unique _)) ⟩∘⟨refl
}
where
open ⇒-Reasoning 𝒟.U
open 𝒟.Equiv
open 𝒟.HomReasoning
open 𝒞 using (¡-unique)
Decorate : Functor Cospans DecoratedCospans
Decorate = record
{ F₀ = idf
; F₁ = decorate
; identity = identity
; homomorphism = homomorphism
; F-resp-≈ = F-resp-≈
}
module ⊗ = Functor (⊗ 𝒞)
module ⊗′ = Functor (⊗′ 𝒞 F)
open 𝒞 using (_+₁_)
Decorate-resp-⊗ : DecoratedCospans [ decorate (⊗.₁ (f , g)) ≈ ⊗′.₁ (decorate f , decorate g) ]
Decorate-resp-⊗ {f = f} {g = g} = record
{ cospans-≈ = Cospans.Equiv.refl
; same-deco = same-deco
}
where
open Cospan f using (N)
open Cospan g using () renaming (N to M)
open 𝒟 using (U; monoidal; _⊗₁_; unitorˡ-commute-from) renaming (module unitorˡ to λ-)
open 𝒞 using (¡; ⊥; ¡-unique; pushout) renaming ([_,_] to [_,_]′; _+₁_ to infixr 10 _+₁_ )
open Category U
open Equiv
open ⇒-Reasoning U
open ⊗-Reasoning monoidal
open F.⊗-homo using () renaming (η to φ; commute to φ-commute)
open F using (F₁; ε)
open Shorthands monoidal
open mc𝒞 using (unitorˡ)
open unitorˡ using () renaming (to to λ⇐′)
same-deco : F₁ 𝒞.id ∘ F₁ ¡ ∘ ε ≈ φ (N , M) ∘ (F₁ ¡ ∘ ε) ⊗₁ (F₁ ¡ ∘ ε) ∘ ρ⇐
same-deco = begin
F₁ 𝒞.id ∘ F₁ ¡ ∘ ε ≈⟨ elimˡ F.identity ⟩
F₁ ¡ ∘ ε ≈⟨ F.F-resp-≈ (¡-unique _) ⟩∘⟨refl ⟩
F₁ (¡ +₁ ¡ 𝒞.∘ λ⇐′) ∘ ε ≈⟨ refl⟩∘⟨ introʳ λ-.isoʳ ⟩
F₁ (¡ +₁ ¡ 𝒞.∘ λ⇐′) ∘ ε ∘ λ⇒ ∘ λ⇐ ≈⟨ refl⟩∘⟨ refl⟩∘⟨ refl⟩∘⟨ coherence-inv₃ monoidal ⟩
F₁ (¡ +₁ ¡ 𝒞.∘ λ⇐′) ∘ ε ∘ λ⇒ ∘ ρ⇐ ≈⟨ refl⟩∘⟨ extendʳ unitorˡ-commute-from ⟨
F₁ (¡ +₁ ¡ 𝒞.∘ λ⇐′) ∘ λ⇒ ∘ id ⊗₁ ε ∘ ρ⇐ ≈⟨ pushˡ F.homomorphism ⟩
F₁ (¡ +₁ ¡) ∘ F₁ λ⇐′ ∘ λ⇒ ∘ id ⊗₁ ε ∘ ρ⇐ ≈⟨ refl⟩∘⟨ extendʳ (switch-fromtoˡ ([ F.F ]-resp-≅ unitorˡ) F.unitaryˡ) ⟨
F₁ (¡ +₁ ¡) ∘ φ (⊥ , ⊥) ∘ ε ⊗₁ id ∘ id ⊗₁ ε ∘ ρ⇐ ≈⟨ refl⟩∘⟨ refl⟩∘⟨ pullˡ (sym serialize₁₂) ⟩
F₁ (¡ +₁ ¡) ∘ φ (⊥ , ⊥) ∘ ε ⊗₁ ε ∘ ρ⇐ ≈⟨ extendʳ (φ-commute (¡ , ¡)) ⟨
φ (N , M) ∘ F₁ ¡ ⊗₁ F₁ ¡ ∘ ε ⊗₁ ε ∘ ρ⇐ ≈⟨ refl⟩∘⟨ pullˡ (sym ⊗-distrib-over-∘) ⟩
φ (N , M) ∘ (F₁ ¡ ∘ ε) ⊗₁ (F₁ ¡ ∘ ε) ∘ ρ⇐ ∎
|