On Mon, Sep 30, 2013 at 1:06 PM, Alan Buxton
Hi****
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I have something like this – purpose is that I need to drop redundant .0 in a whole number – so to show 1.2345 as 1.2345 and to show 1.0 as 1****
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*module Test where*
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*niceShow x = if (isInt x) then show (floor x) else show x*
* *
*isInt x = x == fromInteger (floor x)*****
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But the hlint in my vim plugin keeps warning me that****
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test.hs|3 col 38 warning| Defaulting the following constraint(s) to type `Integer'****
|| (Integral a0) arising from a use of `floor' at /tmp/test.hs:3:38-42****
|| (Show a0) arising from a use of `show' at /tmp/test.hs:3:32-35****
|| In the first argument of `show', namely `(floor x)'****
|| In the expression: show (floor x)****
|| In the expression: if (isInt x) then show (floor x) else show x****
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What does this mean? And what would I need to do in order to prevent this warning?****
It looks like you have a type mismatch in `isInt`, floor returns a type in the typeclass Integral (this may or may not be an Integer) but fromInteger demands its input be an Integer. Here are the type sigs: ghci> :t floor floor :: (Integral b, RealFrac a) => a -> b ghci> :t fromIntegral fromIntegral :: (Integral a, Num b) => a -> b Changing `fromInteger` to `fromIntegeral` should fix this problem. It will also help if you write down type signatures explicitly for your two functions. -- Benjamin Jones