Plan A does seem better. Speaking of making changes to Typeable, is there a chance of connecting/converting between Data.Typeable.TypeRep and Language.Haskell.TH.Type? Oren Ben-Kiki On Wed, Oct 3, 2012 at 3:03 PM, Edward Kmett <ekmett@gmail.com> wrote:
I'm definitely in favor of Plan A.
-Edward
On Wed, Oct 3, 2012 at 8:01 AM, Simon Peyton-Jones <simonpj@microsoft.com>wrote:
* If we do make Typeable instances by default, there are two paths Plan A (easy): make GHC derive Typeable for everything, deprecate all uses of 'deriving Typeable'. Small downside: some programs that are currently rejected will be accepted.
Plan B (tiresome): have AutoDeriveTypable as an extension. That means maintaining the massive instance table.
Personally I vote for Plan A. It's easier and more efficient to implement, and the upside of Plan B is modest in the extreme.