39 lines
1.1 KiB
Agda
39 lines
1.1 KiB
Agda
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module Showable where
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open import Data.String using (String; _++_)
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open import Data.Nat using (ℕ)
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open import Data.Nat.Show using () renaming (show to showNat)
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open import Data.Fin using (Fin)
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open import Data.Fin.Show using () renaming (show to showFin)
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open import Data.Product using (_×_; _,_)
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open import Data.Unit using (⊤; tt)
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record Showable {a} (A : Set a) : Set a where
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field
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show : A → String
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open Showable {{ ... }} public
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instance
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showableString : Showable String
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showableString = record { show = λ s → "\"" ++ s ++ "\"" }
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showableNat : Showable ℕ
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showableNat = record { show = showNat }
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showableFin : ∀ {n : ℕ} → Showable (Fin n)
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showableFin = record { show = showFin }
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showableProd : ∀ {a b} {A : Set a} {B : Set b}
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{{ showableA : Showable A }} {{ showableB : Showable B }} →
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Showable (A × B)
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showableProd {{ showableA }} {{ showableB }} = record
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{ show = λ (a , b) →
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"(" ++ show a ++
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", " ++ show b ++
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")"
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}
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showableUnit : Showable ⊤
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showableUnit = record { show = λ tt → "()" }
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