[Haskell-cafe] Problem with cabal-install where package requires* mutually exclusive versions of another package

[Duncan Coutts]

On Sat, 2009-03-14 at 10:02 -0600, Denis Bueno wrote:
> On Sat, Mar 14, 2009 at 09:40, Duncan Coutts
> <duncan.coutts at worc.ox.ac.uk> wrote:
> > A medium term solution here should involve letting packages specify that
> > some of their dependencies are private, ie nothing is re-exported and
> > thus there is no danger of clashes.
> 
> Is the long term solution to automatically detect what is exported?
> It seems feasible, since I think that is a totally static property,
> no?

Right I think the long term solution is something that involves
identifying packages as functors/signatures and doing subtyping and
unification to check if packages can be composed.

Duncan