Re: Changes to Typeable

On Tue, Feb 14, 2012 at 11:18 AM, Iavor Diatchki wrote:

Hello,

On Mon, Feb 13, 2012 at 5:32 PM, Edward Kmett 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. -Edward