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Fixed-point combinators using iso-recursive types
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| newtype Rec a = Fold { unfold :: Rec a -> a } | |
| fix :: (a -> a) -> a | |
| fix f = (\x -> f (unfold x x)) (Fold (\x -> f (unfold x x))) |
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| newtype Rec a = Fold (Rec a -> a) | |
| unfold :: forall a. Rec a -> Rec a -> a | |
| unfold (Fold x) = x | |
| fix :: forall a b. ((a -> b) -> a -> b) -> a -> b | |
| fix f = (\x -> f (\v -> unfold x x v)) (Fold (\x -> f (\v -> unfold x x v))) |
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