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fake agda for preorder theory
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record Preorder (A : Set) : Set1 where | |
_≤_ : A → A → Set | |
refl : {a} → a ≤ a | |
trans : {a b c} → a ≤ b → b ≤ c → a ≤ c | |
record is-lub {A} (P : Preorder A) {I} (a : I → A) (⋁a : A) : Set where | |
bound : (i : I) → a i ≤ ⋁a | |
least : (b : A) → ((i : I) → a i ≤ b) → ⋁a ≤ b | |
module _ {A B} (P : Preorder A) (Q : Preorder B) (f : A → B) where | |
mono : Set | |
mono = {x y} → x P.≤ y → f x Q.≤ f y | |
ωcont : Set | |
ωcont = (x : ℕ → A) → (i ≤ j → x i P.≤ x j) → -- Gimme an ω-chain xᵢ | |
(⋁x : A) → is-lub P x ⋁x → -- and its limit ⋁ᵢ xᵢ | |
is-lub Q (f ∘ x) (f ⋁x) -- then f(⋁ᵢ xᵢ) = ⋁ᵢ xᵢ |
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