agda-spa/Map.agda

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open import Relation.Binary.PropositionalEquality as Eq using (_≡_; refl)
open import Relation.Binary.Definitions using (Decidable)
open import Relation.Binary.Core using (Rel)
open import Relation.Nullary using (Dec; yes; no)
open import Agda.Primitive using (Level; _⊔_)
module Map {a b : Level} (A : Set a) (B : Set b)
(≡-dec-A : Decidable (_≡_ {a} {A}))
where
open import Data.Nat using ()
open import Data.String using (String; _++_)
open import Data.List using (List; []; _∷_)
open import Data.List.Membership.Propositional using ()
open import Data.Product using (_×_; _,_; Σ)
open import Data.Unit using ()
open import Data.Empty using ()
Map : Set (a b)
Map = List (A × B)
insert : (B B B) A B Map Map
insert f k v [] = (k , v) []
insert f k v (x@(k' , v') xs) with ≡-dec-A k k'
... | yes _ = (k , f v v') xs
... | no _ = x insert f k v xs
foldr : {c} {C : Set c} (A B C C) -> C -> Map -> C
foldr f b [] = b
foldr f b ((k , v) xs) = f k v (foldr f b xs)
_∈_ : (A × B) Map Set (a b)
_∈_ p m = Data.List.Membership.Propositional._∈_ p m
subset : (_≈_ : B B Set b) Map Map Set (a b)
subset _≈_ m₁ m₂ = (k : A) (v : B) (k , v) m₁ Σ B (λ v' v v' × ((k , v') m₂))
lift : (_≈_ : B B Set b) Map Map Set (a b)
lift _≈_ m₁ m₂ = (m₁ m₂) × (m₂ m₁)
where
_⊆_ : Map Map Set (a b)
_⊆_ = subset _≈_