30 lines
724 B
Text
30 lines
724 B
Text
--| `build` is the inverse of `fold`
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let build
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: ∀(a : Type) →
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(∀(list : Type) → ∀(cons : a → list → list) → ∀(nil : list) → list) →
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List a
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= List/build
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let example0 =
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assert
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: build
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Text
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( λ(list : Type) →
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λ(cons : Text → list → list) →
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λ(nil : list) →
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cons "ABC" (cons "DEF" nil)
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)
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≡ [ "ABC", "DEF" ]
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let example1 =
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assert
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: build
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Text
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( λ(list : Type) →
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λ(cons : Text → list → list) →
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λ(nil : list) →
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nil
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)
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≡ ([] : List Text)
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in build
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