22 lines
464 B
Agda
22 lines
464 B
Agda
module 0Trinitarianism.Quest1 where
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open import 0Trinitarianism.Preambles.P1
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isEven : ℕ → Type
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isEven zero = ⊤
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isEven (suc zero) = ⊥
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isEven (suc (suc n)) = isEven n
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{-
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This is a comment block.
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Remove this comment block and formulate
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'there exists an even natural' here.
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-}
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_×_ : Type → Type → Type
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A × C = Σ A (λ a → C)
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div2 : Σ ℕ isEven → ℕ
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div2 (zero , snd₁) = zero
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div2 (suc (suc fst₁) , snd₁) = suc (div2 (fst₁ , snd₁))
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