Re: [Haskell-cafe] instance Binary UTCTime (Was: Oprhan instances)

On Sun, 2009-11-29 at 16:42 -0500, David Menendez wrote:

On Sun, Nov 29, 2009 at 8:37 AM, Duncan Coutts wrote:

...

On Thu, 2009-11-26 at 16:40 -0500, David Menendez wrote:

...

The problem with this solution is that it doesn't scale. If we have M packages providing types and N packages providing classes, then we need M*N additional packages for orphans.

The best long-term solution is probably extending Cabal to handle this more transparently, perhaps by allowing packages to depend on flagged versions of other packages (e.g., foomonad >= 4.0 && < 4.1 && HAS_MTL)

Not going to happen. Such packages could not be translated into binary distro packages.

Do you mean that specific idea won't happen, or that no attempt will be made to reduce the orphan problem?

I mean specifically proposal to change the Cabal package semantics such that they cannot be translated into native system binary packages on various platforms. It's vital to distributing our work that we can produce sensible binary packages on the platforms that people want to use. I should also note that distros will not look kindly on solutions that require N * M separate packages. Duncan