[core libraries] Future of "Text.Show.Functions" module

[Carter Schonwald]

agreed, i'm strongly  -1 on forcing a generic catchall a->b instance,
especially since things like   Show a =>  Show (Bool -> a) , are pretty
useful!

On Wed, Oct 22, 2014 at 4:46 PM, Ganesh Sittampalam <ganesh at earth.li> wrote:

> What's the benefit of this implementation of Show (a -> b)? Even if it
> causes the output to be parseable, it's unlikely to typecheck.
>
> On 20/10/2014 22:00, Andreas Abel wrote:
> > Strongly +1 for Show printing valid Haskell.
> >
> > I'd implement showing for functions as
> >
> >   data Function = Function
> >
> >   instance Show (a -> b) where
> >     show f = "Function"
> >
> > (I would not assume Haskellers expect a Show-ed function to be
> Read-able.)
> >
> > For simple user-friendly display we should add a class to
> Text.PrettyPrint
> >
> >   class Pretty a where
> >     pretty     :: a -> Doc
> >     pretty     = text . prettyShow
> >
> >     prettyShow :: a -> String
> >     prettyShow = render . pretty
> >
> > This class should become standard for implementing simple pretty
> > printing (instead of the abuse of Show).
> >
> > Cheers,
> > Andreas
> >
> >
> > On 19.10.2014 17:36, Brandon Allbery wrote:
> >> On Sun, Oct 19, 2014 at 8:59 AM, Michael Snoyman <michael at snoyman.com
> >> <mailto:michael at snoyman.com>> wrote:
> >>
> >>     I think this really brings up the question of what `Show` should be
> >>     used for. If the goal is to be simple serialization with `Read` as
> >>     the inverse[1], then this is clearly a nonsense instance and
> >>     shouldn't be included.
> >>
> >>
> >> I think I've said before that it would be nice if we had a specific
> >> class for debugging displays, given that Read/Show are generally
> >> oriented toward serialization. Sadly, this would end up requiring a lot
> >> of repetition, since you couldn't sanely fall back on a default Show
> >> instance to get a notional Gist (or whatever) instance.
> >
> >
> >
>
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