[Haskell-beginners] Show for Parameterized Type

[Hartmut]

My early intention was to limit the EW data type to showable/readable
values. It wanted it to only accepting one of these.
Now I have even two alternatives to choose :-)
Thanks
Hartmut

On Mon, Aug 8, 2011 at 12:02 AM, David Place <d at vidplace.com> wrote:

>
> On Aug 7, 2011, at 5:54 PM, Hartmut wrote:
>
> David,
> that was fast :-) Thank you for your help!
> Hartmut
>
>
> Your welcome.  ;-)  I needed the break from what I was doing.  I think I
> actually would like to add that normally i wouldn't put the class
> constraints in the data type definition.
>
> module Main where
>
> data EW a = EW a
>
> x01 = EW 20
> x02 = EW "Test"
>
> instance (Show a) => Show (EW a) where
>   show (EW x) = show "EW:" ++ show x
>
> instance (Read a) =>  Read (EW a) where
>     read (etc...)
>
> ____________________
> David Place
> Owner, Panpipes Ho! LLC
> http://panpipesho.com
> d at vidplace.com
>
>
>
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