Fwd: [Haskell-cafe] Data.Tree.Zipper in the standard libraries

[Neil Mitchell]

Hi

> On the other hand, having something available in the containers package
> for everyone to experiment with seems a good way to evolve towards a
> better design.
>
> I'd still vote for adding the module, and flag it with "experimental"
> stability if
> there are worries of instability.

If you want to mark it as experimental, it should not be in the core
libraries. Evolving designs are great, but libraries@ should not be
the maintainer of such a module. I'm not sure if that is a general
policy, but I would be surprised to hear if it was a minority opinion.

> Well if this is the common agreement then I will withdraw my proposal.
> Maintaining a single module package floating around is too much effort
> for me. I prefer to keep a local copy in the projects that need it
> instead of maintaining an extra dependencies and to force the users to
> download extra software. I am sorry for the wasted time and effort.

I think that's a real shame. Maintaining a cabal package is relatively
little effort. I have several packages which are just one module long
(see for example Safe - which is not only one module, but every
definition within it is only one line!). With cabal-install, the extra
effort to install dependencies is literally nothing - its all handled
automatically. And once you've got some users, and some varied
experience of using the library, then I think making a library
proposal would be a good idea.

Thanks

Neil