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@ -305,4 +305,3 @@ TSWLatexianTemp*
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*.agdai
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*.agdai
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MAlonzo/**
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MAlonzo/**
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*.html
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agda/Agda.css
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.PHONY: all clean
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all: agda
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make pandoc
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open:
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firefox ./public/algebra.html
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agda: Everything.agda
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agda --html --html-dir=public algebra.lagda.md --html-highlight=auto -i.
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rm -f public/Agda.css
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cp Agda.css public/Agda.css
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pandoc: public/*.md
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@$(foreach file,$^, \
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pandoc $(file) -s --to=html+TEX_MATH_DOLLARS --mathjax -c Agda.css -o $(file:.md=.html) ; \
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)
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clean:
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rm -f Everything.agda
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rm -rf public/*
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find . -name '*.agdai' -exec rm \{\} \;
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Everything.agda:
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git ls-tree --full-tree -r --name-only HEAD | egrep '^src/[^\.]*.l?agda(\.md)?' | sed -e 's|^src/[/]*|import |' -e 's|/|.|g' -e 's/.agda//' -e '/import Everything/d' -e 's/..md//' | LC_COLLATE='C' sort > Everything.agda
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@ -1,486 +0,0 @@
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```agda
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open import equality
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module algebra where
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```
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# Algebra of programming
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## Preliminaries (Types, Lemmas, Functions)
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```agda
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id : ∀ {A : Set} → A → A
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id a = a
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_! : ∀ {A B : Set} → (b : B) → A → B
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(b !) _ = b
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```
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We will need functional extensionality
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```agda
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postulate
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extensionality : ∀ {A B : Set} (f g : A → B) → (∀ (x : A) → f x ≡ g x) → f ≡ g
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ext-rev : ∀ {A B : Set} {f g : A → B} → f ≡ g → (∀ (x : A) → f x ≡ g x)
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ext-rev {A} {B} {f} {g} refl x = refl
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```
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Function composition and some facts about it
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```agda
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infixr 9 _∘_
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_∘_ : ∀ {A B C : Set} (g : B → C) (f : A → B) → A → C
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(g ∘ f) x = g (f x)
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{-# INLINE _∘_ #-}
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identityʳ : ∀ {A B : Set} {f : A → B} → f ∘ id ≡ f
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identityʳ {f} = refl
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identityˡ : ∀ {A B : Set} {f : A → B} → id ∘ f ≡ f
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identityˡ {f} = refl
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_⟩∘⟨_ : ∀ {A B C : Set} {g i : B → C} {f h : A → B} → g ≡ i → f ≡ h → g ∘ f ≡ i ∘ h
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refl ⟩∘⟨ refl = refl
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introˡ : ∀ {A B : Set} {f : A → B} {h : B → B} → h ≡ id → f ≡ h ∘ f
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introˡ {f} {h} eq = trans (sym identityˡ) (sym eq ⟩∘⟨ refl)
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introʳ : ∀ {A B : Set} {f : A → B} {h : A → A} → h ≡ id → f ≡ f ∘ h
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introʳ {f} {h} eq = trans (sym identityʳ) (refl ⟩∘⟨ sym eq)
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```
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## Unit and void type
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```agda
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data ⊤ : Set where
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unit : ⊤
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data ⊥ : Set where
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¡ : ∀ {B : Set} → ⊥ → B
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¡ ()
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¡-unique : ∀ {B : Set} → (f : ⊥ → B) → f ≡ ¡
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¡-unique f = extensionality f ¡ (λ ())
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```
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## Products
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```agda
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infixr 8 _×_
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infixr 7 _×₁_
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record _×_ (A B : Set) : Set where
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constructor _,_
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field
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outl : A
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outr : B
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open _×_
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×-cong : ∀ {A B : Set} {x y : A} {u v : B} → x ≡ y → u ≡ v → (x , u) ≡ (y , v)
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×-cong refl refl = refl
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⟨_,_⟩ : {A B C : Set} → (A → B) → (A → C) → A → B × C
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⟨ f , g ⟩ x = (f x) , (g x)
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project₁ : ∀ {A B C : Set} (f : A → B) (g : A → C) → outl ∘ ⟨ f , g ⟩ ≡ f
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project₁ _ _ = refl
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project₂ : ∀ {A B C : Set} (f : A → B) (g : A → C) → outr ∘ ⟨ f , g ⟩ ≡ g
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project₂ _ _ = refl
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⟨⟩-cong : {A B C : Set} → (f g : A → B) → (h i : A → C) → f ≡ g → h ≡ i → ⟨ f , h ⟩ ≡ ⟨ g , i ⟩
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⟨⟩-cong f g h i refl refl = refl
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⟨⟩-unique : ∀ {A B C : Set} (f : A → B) (g : A → C) (h : A → B × C) → outl ∘ h ≡ f → outr ∘ h ≡ g → h ≡ ⟨ f , g ⟩
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⟨⟩-unique f g h refl refl = refl
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_×₁_ : ∀ {A B C D : Set} (f : A → C) (g : B → D) → A × B → C × D
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_×₁_ f g (x , y) = f x , g y
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```
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Composition as function on products
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```agda
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comp : ∀ {A B C : Set} → ((A → B) × (B → C)) → A → C
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comp (f , g) x = g (f x)
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```
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curry, uncurry, eval
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```agda
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curry : ∀ {A B C : Set} → (A × B → C) → (A → B → C)
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curry f a b = f (a , b)
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uncurry : ∀ {A B C : Set} → (A → B → C) → (A × B → C)
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uncurry f (a , b) = f a b
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ev : ∀ {A B : Set} → (A → B) × A → B
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ev (f , a) = f a
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```
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**HOMEWORK 1**
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```agda
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curry-uncurry : ∀ {A B C : Set} → curry ∘ uncurry {A} {B} {C} ≡ id
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curry-uncurry = extensionality (curry ∘ uncurry) id λ _ → refl
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uncurry-curry : ∀ {A B C : Set} → uncurry ∘ curry {A} {B} {C} ≡ id
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uncurry-curry = extensionality (uncurry ∘ curry) id λ _ → refl
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```
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## Naturals
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```agda
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data ℕ : Set where
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zero : ℕ
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succ : ℕ → ℕ
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{-# BUILTIN NATURAL ℕ #-}
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data 𝔹 : Set where
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true : 𝔹
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false : 𝔹
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{-# BUILTIN BOOL 𝔹 #-}
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succ-inj : ∀ {x y : ℕ} → succ x ≡ succ y → x ≡ y
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succ-inj refl = refl
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-- todo rewrite foldn to use ugly cartesian product...
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foldn : ∀ {C : Set} → (C × (C → C)) → ℕ → C
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foldn (c , h) zero = c
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foldn (c , h) (succ n) = h (foldn (c , h) n)
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foldn-id : foldn (zero , succ) ≡ id {ℕ}
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foldn-id = extensionality (foldn (zero , succ)) id helper
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where
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helper : (x : ℕ) → foldn (zero , succ) x ≡ id x
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helper zero = refl
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helper (succ n) rewrite helper n = refl
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foldn-fusion : ∀ {C C' : Set} (c : C) (h : C → C) (k : C → C') (c' : C') (h' : C' → C') → k c ≡ c' → k ∘ h ≡ h' ∘ k → k ∘ foldn (c , h) ≡ foldn (c' , h')
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foldn-fusion {C} {C'} c h k c' h' refl eq = extensionality (k ∘ foldn (c , h)) (foldn (k c , h')) helper
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where
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helper : (x : ℕ) → (k ∘ foldn (c , h)) x ≡ foldn (k c , h') x
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helper zero = refl
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helper (succ x) = begin
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(k ∘ h) (foldn (c , h) x) ≡⟨ ext-rev eq (foldn (c , h) x) ⟩
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(h' ∘ k) (foldn (c , h) x) ≡⟨ cong h' (helper x) ⟩
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h' (foldn (k c , h') x) ∎
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```
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### proving with the fusion law
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```agda
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add : ℕ → ℕ → ℕ
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add zero n = n
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add (succ m) n = succ (add m n)
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plus : ℕ → ℕ → ℕ
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plus n = foldn (n , succ)
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plus' : ℕ → ℕ → ℕ
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plus' = foldn (id , (comp ∘ ⟨ id , succ ! ⟩))
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plus-test1 : plus 13 19 ≡ 32
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plus-test1 = refl
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+ : ℕ × ℕ → ℕ
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+ = uncurry (foldn (id , (comp ∘ ⟨ id , succ ! ⟩)))
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+-test1 : + (3 , 5) ≡ 8
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+-test1 = refl
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+-test2 : + (0 , 100) ≡ 100
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+-test2 = refl
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+-test3 : + (100 , 0) ≡ 100
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+-test3 = refl
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+0 : ∀ (n : ℕ) → + (n , 0) ≡ n
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+0 zero = refl
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+0 (succ n) rewrite +0 n = refl
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-- TODO define with fusion la
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plus-succˡ : ∀ {m n : ℕ} → succ (plus m n) ≡ plus (succ m) n
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plus-succˡ {m} {zero} = refl
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plus-succˡ {m} {succ n} rewrite plus-succˡ {m} {n} = refl
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plus-comm : ∀ {m n : ℕ} → plus m n ≡ plus n m
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plus-comm {zero} {n} = ext-rev foldn-id n
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plus-comm {succ m} {n} rewrite plus-comm {n} {m} = sym (plus-succˡ {m} {n})
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plus-comm' : ∀ {m n : ℕ} → (plus m) ∘ (plus n) ≡ (plus n) ∘ (plus m)
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plus-comm' {m} {n} = begin
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(plus m) ∘ (foldn (n , succ)) ≡⟨ commute₁ ⟩
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foldn ((plus m n) , succ) ≡⟨ extensionality (foldn ((plus m n) , succ)) (foldn ((plus n m) , succ)) helper ⟩
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foldn ((plus n m) , succ) ≡⟨ sym commute₂ ⟩
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(plus n) ∘ (foldn (m , succ)) ∎
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where
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helper : (x : ℕ) → foldn ((plus m n) , succ) x ≡ foldn ((plus n m) , succ) x
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helper x rewrite plus-comm {m} {n} = refl
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commute₁ = foldn-fusion n succ (plus m) (plus m n) succ refl refl
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commute₂ = foldn-fusion m succ (plus n) (plus n m) succ refl refl
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```
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**HOMEWORK 2**
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```agda
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mul : ℕ → ℕ → ℕ
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mul zero n = zero
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mul (succ m) n = plus n (mul m n)
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mul-test1 : mul 0 3 ≡ 0
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mul-test1 = refl
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mul-test2 : mul 3 15 ≡ 45
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mul-test2 = refl
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mult : (m : ℕ) → ℕ → ℕ
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mult m = foldn (zero , (plus m))
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times : (ℕ × ℕ) → ℕ
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times = uncurry times'
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where
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times' : ℕ → ℕ → ℕ
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times' = foldn ((zero !) , (comp ∘ ⟨ curry ⟨ outr , ev ⟩ , + ! ⟩))
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times-test1 : times (1 , 1) ≡ 1
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times-test1 = refl
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times-test2 : times (123 , 15) ≡ 1845
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times-test2 = refl
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times-test3 : times (5 , 0) ≡ 0
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times-test3 = refl
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```
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**HOMEWORK 3**
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```agda
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fac2 : ℕ → ℕ
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fac2 zero = 1
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fac2 (succ n) = times (n , fac2 n)
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fac : ℕ → ℕ
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fac = outr ∘ fac'
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where
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fac' : ℕ → (ℕ × ℕ)
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fac' = foldn ((zero , succ zero) , ⟨ succ ∘ outl , times ∘ (succ ×₁ id) ⟩)
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fac-test1 : fac 5 ≡ 120
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fac-test1 = refl
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fac-test2 : fac 0 ≡ 1
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fac-test2 = refl
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```
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Proofs from the script
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```agda
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distrib : ∀ (m n x : ℕ) → mult m (plus n x) ≡ plus (mult m n) (mult m x)
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distrib m n x = begin
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mult m (plus n x) ≡⟨ refl ⟩
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mult m (foldn (n , succ) x) ≡⟨ ext-rev commute₁ x ⟩
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foldn ((mult m n) , (plus m)) x ≡⟨ sym (ext-rev commute₂ x) ⟩
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plus (mult m n) (foldn (zero , (plus m)) x) ≡⟨ refl ⟩
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plus (mult m n) (mult m x) ∎
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where
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commute₁ : (mult m) ∘ (foldn (n , succ)) ≡ foldn ((mult m n) , (plus m))
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commute₁ = foldn-fusion n succ (mult m) (mult m n) (plus m) kc kh
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where
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kc : mult m n ≡ mult m n
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kc = refl
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kh : mult m ∘ succ ≡ plus m ∘ mult m
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kh = refl
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commute₂ : (plus (mult m n)) ∘ (foldn (zero , (plus m))) ≡ foldn ((mult m n) , (plus m))
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commute₂ = foldn-fusion zero (plus m) (plus (mult m n)) (mult m n) (plus m) kc (kh m n)
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where
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kc : plus (mult m n) zero ≡ mult m n
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kc = refl
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kh : ∀ (m n : ℕ) → (plus (mult m n)) ∘ (plus m) ≡ (plus m) ∘ (plus (mult m n))
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kh zero zero = refl
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kh (succ m) zero = plus-comm'
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kh m (succ n) = plus-comm'
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induction : ∀ (p : ℕ → 𝔹) → p zero ≡ true → (∀ (n : ℕ) → p (succ n) ≡ p n) → p ≡ true !
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induction p IS IH = begin
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p ≡⟨ introʳ foldn-id ⟩
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p ∘ foldn (zero , succ) ≡⟨ commute₁ ⟩
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foldn (true , id) ≡⟨ sym commute₂ ⟩
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(true !) ∘ foldn (zero , succ) ≡⟨ identityʳ ⟩
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true ! ∎
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||||||
where
|
|
||||||
commute₁ = foldn-fusion zero succ p true id IS (extensionality (p ∘ succ) p IH)
|
|
||||||
commute₂ = foldn-fusion zero succ (true !) true id refl refl
|
|
||||||
```
|
|
||||||
|
|
||||||
## Lists
|
|
||||||
|
|
||||||
```agda
|
|
||||||
data 𝕃 (A : Set) : Set where
|
|
||||||
nil : 𝕃 A
|
|
||||||
cons : (A × 𝕃 A) → 𝕃 A
|
|
||||||
|
|
||||||
foldr : ∀ {A C : Set} → (C × (A × C → C)) → 𝕃 A → C
|
|
||||||
foldr (c , h) nil = c
|
|
||||||
foldr (c , h) (cons (x , xs)) = h (x , foldr (c , h) xs)
|
|
||||||
|
|
||||||
foldr-id : ∀ {A : Set} → foldr (nil , cons) ≡ id {𝕃 A}
|
|
||||||
foldr-id {A} = extensionality (foldr (nil , cons)) id helper
|
|
||||||
where
|
|
||||||
helper : ∀ (x : 𝕃 A) → foldr (nil , cons) x ≡ id x
|
|
||||||
helper nil = refl
|
|
||||||
helper (cons (x , xs)) rewrite helper xs = refl
|
|
||||||
|
|
||||||
foldr-fusion : ∀ {A B B' : Set} (c : B) (h : A × B → B) (k : B → B') (c' : B') (h' : A × B' → B')
|
|
||||||
→ k c ≡ c'
|
|
||||||
→ k ∘ h ≡ h' ∘ (id ×₁ k)
|
|
||||||
→ k ∘ foldr (c , h) ≡ foldr (c' , h')
|
|
||||||
foldr-fusion {A} c h k c' h' kc kh = extensionality (k ∘ foldr (c , h)) (foldr (c' , h')) helper
|
|
||||||
where
|
|
||||||
helper : ∀ (x : 𝕃 A) → k (foldr (c , h) x) ≡ foldr (c' , h') x
|
|
||||||
helper nil = kc
|
|
||||||
helper (cons (x , xs)) rewrite ext-rev kh (x , foldr (c , h) xs) | helper xs = refl
|
|
||||||
|
|
||||||
length : ∀ {A : Set} → 𝕃 A → ℕ
|
|
||||||
length {A} = foldr (zero , h)
|
|
||||||
where
|
|
||||||
h : A × ℕ → ℕ
|
|
||||||
h = succ ∘ outr
|
|
||||||
|
|
||||||
isempty? : ∀ {A : Set} → 𝕃 A → 𝔹
|
|
||||||
isempty? = foldr (true , (false !))
|
|
||||||
|
|
||||||
cat : ∀ {A : Set} → 𝕃 A × 𝕃 A → 𝕃 A
|
|
||||||
cat = uncurry (foldr (id , curry (cons ∘ ⟨ outl ∘ outl , ev ∘ (outr ×₁ id) ⟩)))
|
|
||||||
|
|
||||||
sum : 𝕃 ℕ → ℕ
|
|
||||||
sum = foldr (0 , +)
|
|
||||||
```
|
|
||||||
|
|
||||||
**HOMEWORK 4**
|
|
||||||
|
|
||||||
```agda
|
|
||||||
take : ∀ {A : Set} → ℕ → 𝕃 A → 𝕃 A
|
|
||||||
take zero = nil !
|
|
||||||
take (succ n) = foldr (nil , (cons ∘ (id ×₁ take n)))
|
|
||||||
```
|
|
||||||
|
|
||||||
**HOMEWORK 5**
|
|
||||||
|
|
||||||
We show that the `list` function is functorial:
|
|
||||||
|
|
||||||
```agda
|
|
||||||
list : ∀ {A B : Set} → (A → B) → 𝕃 A → 𝕃 B
|
|
||||||
list f = foldr (nil , (cons ∘ (f ×₁ id)))
|
|
||||||
|
|
||||||
list-id : ∀ {A : Set} → list id ≡ id {𝕃 A}
|
|
||||||
list-id = foldr-id
|
|
||||||
|
|
||||||
list-homomorphism : ∀ {A B C : Set} (f : A → B) (g : B → C) → (list g) ∘ (list f) ≡ list (g ∘ f)
|
|
||||||
list-homomorphism {A} {B} {C} f g = foldr-fusion nil (cons ∘ (f ×₁ id)) (list g) nil (cons ∘ ((g ∘ f) ×₁ id)) refl refl
|
|
||||||
```
|
|
||||||
|
|
||||||
**HOMEWORK 6**
|
|
||||||
|
|
||||||
Ackermann function:
|
|
||||||
|
|
||||||
```agda
|
|
||||||
ack : ℕ × ℕ → ℕ
|
|
||||||
ack = uncurry (foldn (succ , h))
|
|
||||||
where
|
|
||||||
-- https://arxiv.org/pdf/1602.05010.pdf
|
|
||||||
-- first look
|
|
||||||
h' : (ℕ → ℕ) → ℕ → ℕ
|
|
||||||
h' f = foldn (f 1 , f)
|
|
||||||
-- pointfree
|
|
||||||
h : (ℕ → ℕ) → ℕ → ℕ
|
|
||||||
h = curry (ev ∘ ((foldn ∘ ⟨ ev ∘ ⟨ id , 1 ! ⟩ , id ⟩) ×₁ id))
|
|
||||||
|
|
||||||
-- pointwise definition for comparison
|
|
||||||
ack' : ℕ → ℕ → ℕ
|
|
||||||
ack' 0 = succ
|
|
||||||
ack' (succ n) zero = ack' n 1
|
|
||||||
ack' (succ n) (succ m) = ack' n (ack' (succ n) m)
|
|
||||||
|
|
||||||
ack-test1 : ack (3 , 3) ≡ ack' 3 3
|
|
||||||
ack-test1 = refl
|
|
||||||
ack-test2 : ack (0 , 3) ≡ ack' 0 3
|
|
||||||
ack-test2 = refl
|
|
||||||
ack-test3 : ack (3 , 2) ≡ ack' 3 2
|
|
||||||
ack-test3 = refl
|
|
||||||
ack-test4 : ack (2 , 2) ≡ ack' 2 2
|
|
||||||
ack-test4 = refl
|
|
||||||
```
|
|
||||||
|
|
||||||
**HOMEWORK 7**
|
|
||||||
|
|
||||||
Trees:
|
|
||||||
|
|
||||||
```agda
|
|
||||||
data 𝕋 (A : Set) : Set where
|
|
||||||
leaf : A → 𝕋 A
|
|
||||||
bin : 𝕋 A × 𝕋 A → 𝕋 A
|
|
||||||
|
|
||||||
foldt : ∀ {A C : Set} → ((A → C) × ((C × C) → C)) → 𝕋 A → C
|
|
||||||
foldt (c , h) (leaf a) = c a
|
|
||||||
foldt (c , h) (bin (s , t)) = h (foldt (c , h) s , foldt (c , h) t)
|
|
||||||
|
|
||||||
front : ∀ {A : Set} → 𝕋 A → 𝕃 A
|
|
||||||
front = foldt ((cons ∘ ⟨ id , nil ! ⟩) , cat)
|
|
||||||
|
|
||||||
foldt-id : ∀ {A : Set} → foldt (leaf , bin) ≡ id {𝕋 A}
|
|
||||||
foldt-id {A} = extensionality (foldt (leaf , bin)) id helper
|
|
||||||
where
|
|
||||||
helper : ∀ (x : 𝕋 A) → foldt (leaf , bin) x ≡ id x
|
|
||||||
helper (leaf x) = refl
|
|
||||||
helper (bin (x , y)) rewrite helper x | helper y = refl
|
|
||||||
|
|
||||||
foldt-fusion : ∀ {A C C' : Set} (c : A → C) (h : C × C → C) (k : C → C') (c' : A → C') (h' : C' × C' → C') → k ∘ c ≡ c' → k ∘ h ≡ h' ∘ (k ×₁ k) → k ∘ foldt (c , h) ≡ foldt (c' , h')
|
|
||||||
foldt-fusion {A} {C} {C'} c h k c' h' kc kh = extensionality (k ∘ foldt (c , h)) (foldt (c' , h')) helper
|
|
||||||
where
|
|
||||||
helper : ∀ (x : 𝕋 A) → k (foldt (c , h) x) ≡ foldt (c' , h') x
|
|
||||||
helper (leaf x) = ext-rev kc x
|
|
||||||
helper (bin (s , t)) rewrite ext-rev kh (foldt (c , h) s , foldt (c , h) t) | helper s | helper t = refl
|
|
||||||
|
|
||||||
```
|
|
||||||
|
|
||||||
**HOMEWORK 8**
|
|
||||||
|
|
||||||
```agda
|
|
||||||
sumt : 𝕋 ℕ → ℕ
|
|
||||||
sumt = foldt (id , +)
|
|
||||||
|
|
||||||
front-sum : sumt ≡ sum ∘ front
|
|
||||||
front-sum = sym (foldt-fusion (cons ∘ ⟨ id , nil ! ⟩) cat sum id + (extensionality _ _ triangle) square)
|
|
||||||
where
|
|
||||||
triangle : ∀ x → (sum ∘ (cons ∘ ⟨ id , nil ! ⟩)) x ≡ id x
|
|
||||||
triangle x rewrite +0 x = refl
|
|
||||||
square : sum ∘ cat ≡ + ∘ (sum ×₁ sum)
|
|
||||||
square = extensionality _ _ helper
|
|
||||||
where
|
|
||||||
helper : (x : 𝕃 ℕ × 𝕃 ℕ) → (sum ∘ cat) x ≡ (+ ∘ (sum ×₁ sum)) x
|
|
||||||
helper = {! !}
|
|
||||||
```
|
|
||||||
|
|
||||||
**HOMEWORK 9**
|
|
||||||
|
|
||||||
```agda
|
|
||||||
data 𝕋' (A : Set) : Set where
|
|
||||||
leaf' : A → 𝕋' A
|
|
||||||
bin' : A × 𝕋' A × 𝕋' A → 𝕋' A
|
|
||||||
|
|
||||||
foldb : ∀ {A C : Set} → ((A → C) × (A × C × C → C)) → 𝕋' A → C
|
|
||||||
foldb (c , h) (leaf' x) = c x
|
|
||||||
foldb (c , h) (bin' (x , (s , t))) = h (x , (foldb (c , h) s , foldb (c , h) t))
|
|
||||||
|
|
||||||
foldb-id : ∀ {A : Set} → foldb (leaf' , bin') ≡ id {𝕋' A}
|
|
||||||
foldb-id {A} = extensionality (foldb (leaf' , bin')) id helper
|
|
||||||
where
|
|
||||||
helper : ∀ (x : 𝕋' A) → foldb (leaf' , bin') x ≡ id x
|
|
||||||
helper (leaf' x) = refl
|
|
||||||
helper (bin' (x , (t , s))) rewrite helper t | helper s = refl
|
|
||||||
|
|
||||||
foldb-fusion : ∀ {A C C' : Set} (c : A → C) (h : A × C × C → C) (k : C → C') (c' : A → C') (h' : A × C' × C' → C') → k ∘ c ≡ c' → k ∘ h ≡ h' ∘ (id ×₁ k ×₁ k) → k ∘ foldb (c , h) ≡ foldb (c' , h')
|
|
||||||
foldb-fusion {A} {C} {C'} c h k c' h' kc kh = extensionality _ _ helper
|
|
||||||
where
|
|
||||||
helper : ∀ (x : 𝕋' A) → (k ∘ foldb (c , h)) x ≡ foldb (c' , h') x
|
|
||||||
helper (leaf' x) = ext-rev kc x
|
|
||||||
helper (bin' (x , (s , t))) rewrite ext-rev kh (x , (foldb (c , h) s , foldb (c , h) t)) | helper s | helper t = refl
|
|
||||||
|
|
||||||
size : ∀ {A : Set} → 𝕋' A → ℕ
|
|
||||||
size = foldb ((1 !) , (succ ∘ + ∘ outr))
|
|
||||||
|
|
||||||
flatten : ∀ {A : Set} → 𝕋' A → 𝕃 A
|
|
||||||
flatten = foldb ((cons ∘ ⟨ id , nil ! ⟩) , (cons ∘ (id ×₁ cat)))
|
|
||||||
|
|
||||||
flatten-size : ∀ {A : Set} → length ∘ flatten ≡ size {A}
|
|
||||||
flatten-size {A} = foldb-fusion (cons ∘ ⟨ id , nil ! ⟩) (cons ∘ (id ×₁ cat)) length (1 !) (succ ∘ + ∘ outr) refl square
|
|
||||||
where
|
|
||||||
square : length ∘ (cons ∘ ((id ×₁ cat))) ≡ (succ ∘ + ∘ outr) ∘ (id ×₁ length ×₁ length)
|
|
||||||
square = {! !}
|
|
||||||
```
|
|
|
@ -1,35 +0,0 @@
|
||||||
module equality where
|
|
||||||
-- in this module we define propositional equality and some helper syntax.
|
|
||||||
|
|
||||||
infix 4 _≡_
|
|
||||||
data _≡_ {A : Set} (a : A) : A → Set where
|
|
||||||
instance refl : a ≡ a
|
|
||||||
{-# BUILTIN EQUALITY _≡_ #-}
|
|
||||||
|
|
||||||
-- ≡ is a equivalence relation
|
|
||||||
sym : ∀ {A : Set} {x y : A} → x ≡ y → y ≡ x
|
|
||||||
sym refl = refl
|
|
||||||
|
|
||||||
trans : ∀ {A : Set} {x y z : A} → x ≡ y → y ≡ z → x ≡ z
|
|
||||||
trans refl refl = refl
|
|
||||||
|
|
||||||
cong : ∀ {A B : Set} (f : A → B) {x y} → x ≡ y → f x ≡ f y
|
|
||||||
cong f refl = refl
|
|
||||||
|
|
||||||
-- Equational reasoning
|
|
||||||
infix 3 _∎
|
|
||||||
infixr 2 _≡⟨⟩_ step-≡
|
|
||||||
infix 1 begin_
|
|
||||||
begin_ : ∀ {A : Set} {x y : A} → x ≡ y → x ≡ y
|
|
||||||
begin x = x
|
|
||||||
|
|
||||||
_≡⟨⟩_ : ∀ {A : Set} (x y : A) → x ≡ y → x ≡ y
|
|
||||||
_ ≡⟨⟩ _ = λ x → x
|
|
||||||
|
|
||||||
_∎ : ∀ {A : Set} (x : A) → x ≡ x
|
|
||||||
_ ∎ = refl
|
|
||||||
|
|
||||||
step-≡ : ∀ {A : Set} (x {y z} : A) → y ≡ z → x ≡ y → x ≡ z
|
|
||||||
step-≡ _ y≡z x≡y = trans x≡y y≡z
|
|
||||||
|
|
||||||
syntax step-≡ x eq1 eq2 = x ≡⟨ eq2 ⟩ eq1
|
|
4
tex/.vscode/ltex.dictionary.en-US.txt
vendored
4
tex/.vscode/ltex.dictionary.en-US.txt
vendored
|
@ -1,4 +0,0 @@
|
||||||
Vatthauer
|
|
||||||
mycase
|
|
||||||
Coalgebras
|
|
||||||
Coalgebra
|
|
27
tex/.vscode/settings.json
vendored
27
tex/.vscode/settings.json
vendored
|
@ -1,27 +0,0 @@
|
||||||
{
|
|
||||||
"latex-workshop.latex.tools": [
|
|
||||||
{
|
|
||||||
"name": "latexmk-main",
|
|
||||||
"command": "latexmk",
|
|
||||||
"args": [
|
|
||||||
"-synctex=1",
|
|
||||||
"-interaction=nonstopmode",
|
|
||||||
"-file-line-error",
|
|
||||||
"-shell-escape",
|
|
||||||
"-pdf",
|
|
||||||
"-xelatex",
|
|
||||||
"-outdir=%OUTDIR%",
|
|
||||||
"main.tex"
|
|
||||||
],
|
|
||||||
"env": {}
|
|
||||||
}
|
|
||||||
],
|
|
||||||
"latex-workshop.latex.recipes": [
|
|
||||||
{
|
|
||||||
"name": "latexmk-main",
|
|
||||||
"tools": [
|
|
||||||
"latexmk-main"
|
|
||||||
]
|
|
||||||
}
|
|
||||||
]
|
|
||||||
}
|
|
15
tex/Makefile
15
tex/Makefile
|
@ -1,15 +0,0 @@
|
||||||
src = $(wildcard *.tex)
|
|
||||||
pdf = $(src:.tex=.pdf)
|
|
||||||
|
|
||||||
.PHONY: all clean
|
|
||||||
|
|
||||||
all: $(pdf)
|
|
||||||
|
|
||||||
%.pdf: %.tex $(wildcard src/*.tex) $(wildcard *.bib)
|
|
||||||
latexmk -pdf -xelatex -shell-escape -file-line-error -synctex=1 -halt-on-error -shell-escape $<
|
|
||||||
|
|
||||||
clean:
|
|
||||||
latexmk -C $(src)
|
|
||||||
rm -f $(wildcard *.out *.nls *.nlo *.bbl *.blg *-blx.bib *.run.xml *.bcf *.synctex.gz *.fdb_latexmk *.fls *.toc *.loe *.tdo *.bbl-SAVE-ERROR)
|
|
||||||
rm -f $(wildcard sections/*.aux)
|
|
||||||
rm -rf $(wildcard _minted-main sections/.auctex-auto _region_.prv)
|
|
117
tex/main.tex
117
tex/main.tex
|
@ -1,117 +0,0 @@
|
||||||
\documentclass[a4paper,11pt,titlepage]{scrartcl}
|
|
||||||
|
|
||||||
%%%% Document Setup
|
|
||||||
\usepackage[top=2cm,lmargin=1in,rmargin=1in,bottom=3cm,hmarginratio=1:1]{geometry}
|
|
||||||
\usepackage{scrlayer-fancyhdr}
|
|
||||||
\usepackage{extramarks}
|
|
||||||
\usepackage{anyfontsize}
|
|
||||||
\usepackage{unicode-math}
|
|
||||||
\usepackage[scale=.85]{noto-mono} % TODO find better unicode mono font
|
|
||||||
\usepackage[final]{hyperref}
|
|
||||||
\pagestyle{fancy}
|
|
||||||
\lhead{\DocTitle}
|
|
||||||
\chead{\UniCourse}
|
|
||||||
\rhead{\firstxmark}
|
|
||||||
\lfoot{\lastxmark}
|
|
||||||
\cfoot{\thepage}
|
|
||||||
\renewcommand\headrulewidth{0.4pt}
|
|
||||||
\renewcommand\footrulewidth{0.4pt}
|
|
||||||
%%%%
|
|
||||||
|
|
||||||
%%%% Metadata
|
|
||||||
\newcommand{\DocTitle}{Lecture notes}
|
|
||||||
\newcommand{\UniCourse}{Algebra of Programming}
|
|
||||||
\newcommand{\UniProf}{Prof.\ Dr.\ Stefan Milius}
|
|
||||||
\author{Leon Vatthauer}
|
|
||||||
%%%%
|
|
||||||
|
|
||||||
%%%% Title
|
|
||||||
\title{
|
|
||||||
\vspace{2in}
|
|
||||||
\textmd{\textbf{\UniCourse\\\DocTitle}}\\
|
|
||||||
\vspace{0.1in}\large{\textit{\UniProf\ }}
|
|
||||||
\vspace{3in}
|
|
||||||
}
|
|
||||||
%%%%
|
|
||||||
|
|
||||||
%%%% Math packages
|
|
||||||
\usepackage{amsthm}
|
|
||||||
\usepackage{thmtools}
|
|
||||||
\usepackage{tikz}
|
|
||||||
\usetikzlibrary{cd, quotes}
|
|
||||||
\declaretheorem[name=Definition,style=definition,numberwithin=section]{definition}
|
|
||||||
\declaretheorem[name=Example,style=definition,sibling=definition]{example}
|
|
||||||
\declaretheorem[style=definition,numbered=no]{exercise}
|
|
||||||
\declaretheorem[name=Remark,style=definition,sibling=definition]{remark}
|
|
||||||
\declaretheorem[name=Assumption,style=definition,sibling=definition]{assumption}
|
|
||||||
\declaretheorem[name=Observation,style=definition,sibling=definition]{observation}
|
|
||||||
\declaretheorem[name=Theorem,sibling=definition]{theorem}
|
|
||||||
\declaretheorem[sibling=definition]{corollary}
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\declaretheorem[name=Fact,sibling=definition]{fact}
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\declaretheorem[sibling=definition]{lemma}
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\declaretheorem[sibling=lemma]{proposition}
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||||||
%%%%
|
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||||||
|
|
||||||
\makeatletter
|
|
||||||
\hypersetup{
|
|
||||||
pdfauthor={\@author},
|
|
||||||
pdftitle={\@title},
|
|
||||||
% kill those ugly red rectangles around links
|
|
||||||
hidelinks,
|
|
||||||
}
|
|
||||||
\makeatother
|
|
||||||
|
|
||||||
%%%% Custom definitions: Commands and environments
|
|
||||||
|
|
||||||
%%% Case distinction environment
|
|
||||||
% Defines the `mycase` environment, copied from https://tex.stackexchange.com/questions/251053/how-to-use-case-1-case-2-in-a-proof-ieee-confs
|
|
||||||
\newcounter{cases}
|
|
||||||
\newcounter{subcases}[cases]
|
|
||||||
\newenvironment{mycase}
|
|
||||||
{
|
|
||||||
\setcounter{cases}{0}
|
|
||||||
\setcounter{subcases}{0}
|
|
||||||
\newcommand{\case}
|
|
||||||
{
|
|
||||||
\par\indent\stepcounter{cases}\textbf{Case \thecases.}
|
|
||||||
}
|
|
||||||
\newcommand{\subcase}
|
|
||||||
{
|
|
||||||
\par\indent\stepcounter{subcases}\textit{Subcase (\thesubcases):}
|
|
||||||
}
|
|
||||||
}
|
|
||||||
{
|
|
||||||
\par
|
|
||||||
}
|
|
||||||
\renewcommand*\thecases{\arabic{cases}}
|
|
||||||
\renewcommand*\thesubcases{\roman{subcases}}
|
|
||||||
%%%
|
|
||||||
|
|
||||||
%%% Custom label command
|
|
||||||
\makeatletter
|
|
||||||
\newcommand{\customlabel}[2]{%
|
|
||||||
\protected@write \@auxout {}{\string \newlabel {#1}{{#2}{\thepage}{#2}{#1}{}} }% chktex 1
|
|
||||||
\hypertarget{#1}{#2}%
|
|
||||||
}
|
|
||||||
\makeatother
|
|
||||||
%%%
|
|
||||||
%%%%
|
|
||||||
|
|
||||||
|
|
||||||
\begin{document}
|
|
||||||
%% Titlepage
|
|
||||||
\maketitle
|
|
||||||
\setcounter{page}{1}
|
|
||||||
%%
|
|
||||||
|
|
||||||
%% TOC
|
|
||||||
\tableofcontents
|
|
||||||
\pagebreak
|
|
||||||
%%
|
|
||||||
|
|
||||||
%% Contents
|
|
||||||
\include{sections/01_introduction}
|
|
||||||
\include{sections/02_categories}
|
|
||||||
\include{sections/03_constructions}
|
|
||||||
%%
|
|
||||||
\end{document}
|
|
|
@ -1,4 +0,0 @@
|
||||||
\section{Introduction}
|
|
||||||
|
|
||||||
\subsection{Functions}
|
|
||||||
\subsection{Data Types}
|
|
|
@ -1,9 +0,0 @@
|
||||||
\section{Category Theory}
|
|
||||||
|
|
||||||
\subsection{Special Objects}
|
|
||||||
\subsection{Duality}
|
|
||||||
\subsection{Functors}
|
|
||||||
\subsection{Natural Transformations}
|
|
||||||
\subsection{Functor Algebras}
|
|
||||||
\subsection{Functor Coalgebras}
|
|
||||||
\subsection{(co)Limits} % chktex 36
|
|
|
@ -1 +0,0 @@
|
||||||
\section{Functions and Data}
|
|
|
@ -1,4 +0,0 @@
|
||||||
\section{Constructions}
|
|
||||||
\subsection{CPO}
|
|
||||||
\subsection{Initial Algebra Construction}
|
|
||||||
\subsection{Terminal Coalgebra Construction}
|
|
Loading…
Reference in a new issue