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20 lines
393 B
20 lines
393 B
module Hypo where |
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import Control.Monad.Trans.Reader |
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import Control.Monad.Trans.Maybe |
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-- r -> Maybe a |
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foo :: Int -> ReaderT Int Maybe Int |
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foo a = return a |
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-- (Reader r) (Maybe a) |
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-- r -> Maybe a |
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bar :: Int -> MaybeT (Reader Int) Int |
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bar a = return a |
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-- looks pretty much the same to me... |
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main :: IO () |
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main = do |
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print $ runReaderT (foo 1) 5 |
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print $ runReader (runMaybeT (bar 1)) 5 |