27 lines
521 B
Text
27 lines
521 B
Text
data Maybe () where {
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Nothing : Maybe ()
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Just : Int -> Maybe ()
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};
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-- fmap : (Int -> Int) -> Maybe () -> Maybe () ;
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-- fmap f ma = case ma of {
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-- Nothing => Nothing ;
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-- Just a => Just (f a) ;
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-- };
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main = case (Just 5) of {
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Just a => a ;
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Nothing => 1 ;
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_ => 66 ;
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};
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-- pure : Int -> Maybe () ;
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-- pure x = Just x ;
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--
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-- return = pure;
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--
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-- bind : Maybe () -> (Int -> Maybe ()) -> Maybe () ;
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-- bind ma f = case ma of {
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-- Nothing => Nothing ;
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-- Just a => f a ;
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-- };
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