34 lines
912 B
Haskell
34 lines
912 B
Haskell
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{-# LANGUAGE OverloadedStrings #-}
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module TypeFun where
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import Foo
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import Bar
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import qualified Baz as Bang
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import Data.Typeable
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data Person = Person {
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name :: String,
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address :: String
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}
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main :: IO ()
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main = do
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doSomethingOnType 'c'
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doSomethingOnType (35 :: Integer)
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doSomethingOnType "a string"
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doSomethingOnType :: Typeable a => a -> IO ()
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doSomethingOnType a = case show (typeOf a) of
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"Char" -> print $ performActionOnChar a
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"Integer" -> print $ performActionOnInt a
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_ -> print "undefined!"
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performActionOnChar :: Typeable a => a -> String
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performActionOnChar a = case cast a :: Maybe Char of
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Just c -> "Concatenating with string: " ++ [c]
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Nothing -> "Cast went wrong..."
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performActionOnInt :: Typeable a => a -> String
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performActionOnInt a = case cast a :: Maybe Integer of
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Just i -> "Concatenating with string: " ++ show (i + 10)
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Nothing -> "Cast went wrong..."
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