what coercion can i use to get the below program to compile? i see class (Real a, Fractional a) => RealFrac a where round :: (Integral b) => a -> b and class (Fractional a) => Floating a where sqrt :: a -> a various combinations of fromInteger, toInteger do not help. fnK_ :: Int -> Int fnK_ x = round (sqrt x) -- line 2 Hugs session for: H:\Program Files\Hugs98\lib\Prelude.hs Prelude> :load xva Reading file "xva.hs": Type checking ERROR "xva.hs":2 - Instances of (RealFrac Int, Floating Int) required for definition of fnK_ __________________________________ Do you Yahoo!? Yahoo! Mail - Find what you need with new enhanced search. http://info.mail.yahoo.com/mail_250
James, Untested: fnK_ :: Int -> Int fnK_ n = round (sqrt $ fromInteger x :: Double) HTH, Stefan
fnK_ :: Int -> Int fnK_ = round . sqrt . fromIntegral james pentland wrote:
what coercion can i use to get the below program to compile?
i see class (Real a, Fractional a) => RealFrac a where round :: (Integral b) => a -> b
and class (Fractional a) => Floating a where sqrt :: a -> a
various combinations of fromInteger, toInteger do not help.
fnK_ :: Int -> Int fnK_ x = round (sqrt x) -- line 2
Hugs session for: H:\Program Files\Hugs98\lib\Prelude.hs Prelude> :load xva Reading file "xva.hs": Type checking ERROR "xva.hs":2 - Instances of (RealFrac Int, Floating Int) required for definition of fnK_
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james pentland wrote:
what coercion can i use to get the below program to compile? ... various combinations of fromInteger, toInteger do not help.
Did you try fromIntegral? fromIntegral :: (Integral a, Num b) => a -> b
fnK_ :: Int -> Int fnK_ x = round (sqrt x) -- line 2
-- Thomas H
participants (4)
-
james pentland -
Lennart Augustsson -
Stefan Holdermans -
Thomas Hallgren