Changes to Typeable
ekmett at gmail.com
Tue Feb 14 21:33:22 CET 2012
On Tue, Feb 14, 2012 at 11:18 AM, Iavor Diatchki
<iavor.diatchki at gmail.com>wrote:
> On Mon, Feb 13, 2012 at 5:32 PM, Edward Kmett <ekmett at gmail.com> wrote:
>> There are fewer combinators from commonly used classes for working with
>> the left argument of a bifunctor, however.
> I think that the bifunctor part of Bas's version is a bit of a red
> herring. What I like about it is that it overloads exactly what needs to
> be overloaded---the representation of the type---without the need for any
> fake parameters. To make things concrete, here is some code:
> > newtype TypeRepT t = TR TypeRep
> > class Typeable t where
> > typeRep :: TypeRepT t
> > instacne Typeable Int where typeRep = TR type_rep_for_int
> > instance Typeable  where typeRep = TR type_rep_for_list
I have no problem with this version either, although the Proxy type is
useful for a lot of other purposes, while this type is single use.
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