[Haskell-cafe] question about show

[David Fox]

Show is supposed to convert its argument into a haskell expression which,
when evaluated, returns the same value that was initially passed to show.
 So by this definition, "\252" is just as correct  as "ü".

There are some Show instances out in the world that do not follow this
rule, but they are bad.  I'm looking at you, Network.URI!


On Wed, Mar 5, 2014 at 2:20 PM, <k at ioctl.it> wrote:

>  Okay, it makes somewhat more sense now after reading that thread. But
> technically, why does
>
> show "ü"
>
> not handle Unicode? Isn't the internal representation of [Char] actually
> still Unicode, as per
>
> http://hackage.haskell.org/package/base-4.6.0.1/docs/Data-Char.html
>
> Thanks!
>
> k
>
>
> On Wed, Mar 5, 2014, at 01:46 PM, Clark Gaebel wrote:
>
> "Show" is for debug output. It's not a generic "to_string". See this
> thread [1] from last week for more info.
>
>   - Clark
>
> [1] https://groups.google.com/forum/#!topic/haskell-cafe/32EeI96b1VQ
>
>
> On Wed, Mar 5, 2014 at 4:43 PM, <k at ioctl.it> wrote:
>
> Hello!
>
>  I'm sure this has been answered many times before, but I can't find an
>  explanation for this behavior anywhere. The question I have is a general
>  one regarding 'show'. Why does
>
>  main = do
>      putStrLn "ü"
>
>  ➜  ~ runhaskell test.hs
>  ü
>
>
>  and:
>
>  main = do
>      putStrLn $ show "ü"
>
>  ➜  ~ runhaskell test.hs
>  "\252"
>
>  Thank you all for an enlightening answer already!
>
>  Best,
>
>  k
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>
>
> --
> Clark.
>
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