foldable flexible bridges (putting foldable+traversable in prelude)

[Henning Thielemann]

On Tue, 21 May 2013, Ian Lynagh wrote:

> On Tue, May 21, 2013 at 11:20:28AM -0400, Edward Kmett wrote:
>> One potentially palatable option would be to just note that incorporating these into the a Prelude can be done while leaving the haskell98 and haskell2010 packages with the current behavior.
>
> Wherever feasible, any change to Prelude would not be reflected in
> haskell98:Prelude or haskell2010:Prelude. If we make changes at the same
> time as splitting base, then i think it makes sense to leave an
> unchanged Prelude in base too.

I have to say, I find splitting the base package much more important than 
changing Prelude.