11 lines
219 B
Haskell
11 lines
219 B
Haskell
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-- Generic type
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newtype Data a = Data {value :: a}
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-- Implement generic type conversion of `Data`
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instance Functor Data where
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fmap f (Data val) = Data (f val)
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-- >>> value ((*9) <$> (Data { value = 2 }))
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-- 18
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--
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