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|
{-# OPTIONS -fglasgow-exts -fno-implicit-prelude #-}
module Main where
{
-- import Prelude;
import qualified Prelude;
import Prelude(String,undefined,Maybe(..),IO,putStrLn,Integer,(++),Rational);
debugFunc :: String -> IO a -> IO a;
debugFunc s ioa = (putStrLn ("++ " ++ s)) Prelude.>>
(ioa Prelude.>>= (\a ->
(putStrLn ("-- " ++ s)) Prelude.>> (Prelude.return a)
));
infixl 1 >>=;
infixl 1 >>;
class HasReturn m where
{
return :: a -> m a;
};
class HasBind m n mn | m n -> mn where
{
(>>=) :: m a -> (a -> n b) -> mn b;
};
class HasSeq m n mn | m n -> mn where
{
(>>) :: m a -> n b -> mn b;
};
class HasFail m where
{
fail :: String -> m a;
};
instance HasReturn IO where
{
return a = debugFunc "return" (Prelude.return a);
};
instance HasBind IO IO IO where
{
(>>=) ma amb = debugFunc ">>=" ((Prelude.>>=) ma amb);
};
instance HasSeq IO IO IO where
{
(>>) ma mb = debugFunc ">>" ((Prelude.>>) ma mb);
};
instance HasFail IO where
{
fail s = debugFunc "fail" (Prelude.return undefined);
-- fail s = debugFunc "fail" (Prelude.fail s);
};
class HasFromInteger a where
{
fromInteger :: a -> a;
};
instance HasFromInteger Integer where
{
fromInteger a = a Prelude.+ a Prelude.+ a Prelude.+ a Prelude.+ a; -- five times
};
class HasFromRational a where
{
fromRational :: a -> a;
};
instance HasFromRational Rational where
{
fromRational a = a Prelude.+ a Prelude.+ a; -- three times
};
class HasNegate a where
{
negate :: a -> a;
};
instance HasNegate Integer where
{
negate a = a; -- don't actually negate
};
instance HasNegate Rational where
{
negate a = a; -- don't actually negate
};
class HasMinus a where
{
(-) :: a -> a -> a;
};
instance HasMinus Rational where
{
(-) x y = y; -- changed function
};
instance HasMinus Integer where
{
(-) x y = y; -- changed function
};
test_do f g = do
{
f; -- >>
Just a <- g; -- >>= (and fail if g returns Nothing)
return a; -- return
};
test_fromInteger :: Integer;
test_fromInteger = 27;
test_fromRational :: Rational;
test_fromRational = 31.5;
test_negate :: Integer -> Integer;
test_negate a = - a;
test_fromInteger_pattern :: Integer -> String;
test_fromInteger_pattern a@1 = "1=" ++ (Prelude.show a);
test_fromInteger_pattern a@(-2) = "(-2)=" ++ (Prelude.show a);
test_fromInteger_pattern (a + 7) = "(a + 7)=" ++ Prelude.show a;
test_fromRational_pattern :: Rational -> String;
test_fromRational_pattern a@0.5 = "0.5=" ++ (Prelude.show a);
test_fromRational_pattern a@(-0.7) = "(-0.7)=" ++ (Prelude.show a);
test_fromRational_pattern a = "_=" ++ (Prelude.show a);
doTest :: String -> IO a -> IO ();
doTest s ioa =
(putStrLn ("start test " ++ s))
Prelude.>>
ioa
Prelude.>>
(putStrLn ("end test " ++ s));
main :: IO ();
main =
(doTest "test_do failure"
(test_do (Prelude.return ()) (Prelude.return Nothing))
)
Prelude.>>
(doTest "test_do success"
(test_do (Prelude.return ()) (Prelude.return (Just ())))
)
Prelude.>>
(doTest "test_fromInteger"
(putStrLn (Prelude.show test_fromInteger))
)
Prelude.>>
(doTest "test_fromRational"
(putStrLn (Prelude.show test_fromRational))
)
Prelude.>>
(doTest "test_negate"
(putStrLn (Prelude.show (test_negate 3)))
)
Prelude.>>
(doTest "test_fromInteger_pattern 1"
(putStrLn (test_fromInteger_pattern 1))
)
Prelude.>>
(doTest "test_fromInteger_pattern (-2)"
(putStrLn (test_fromInteger_pattern (-(2::Integer)::Integer)))
)
Prelude.>>
(doTest "test_fromInteger_pattern 9"
(putStrLn (test_fromInteger_pattern 9))
)
Prelude.>>
(doTest "test_fromRational_pattern 0.5"
(putStrLn (test_fromRational_pattern 0.5))
)
Prelude.>>
(doTest "test_fromRational_pattern (-0.7)"
(putStrLn (test_fromRational_pattern (-(0.7::Rational)::Rational)))
)
Prelude.>>
(doTest "test_fromRational_pattern 1.7"
(putStrLn (test_fromRational_pattern 1.7))
);
}
|
