[arch-haskell] Thoughts on Procedure

[Peter Simons]

Hi Don,

 > So we'll always have a consistent set? This would be a valuable list
 > -- no other distro aims for this, other than Debian, which aims only
 > to support a few hundred packages.

the way I see it, Hackage represents the "known universe" of Haskell
packages. That distribution can be accessed by means of Cabal.

Unfortunately, build instructions for Cabal are too sophisticated to be
used directly by other package managers, like Pacman, because these
package managers lack the ability to install several versions of the
same package at the same time.

Now, our task is to map Cabal to Pacman, i.e. we find the most recent
subset of Hackage that can be installed within the boundaries of Pacman.
This ought to be possible in pure computation: the Cabal files contain
everything we need to know.

In theory, this "simple" subset of Hackage can be translated into build
instructions for any number of package managers. If we can generate
PKGBUILD files, chances are that we can generate build instructions for
Gentoo, NixOS, FreeBSD, and whatnot else just the same.

Maybe we should write a cabal2prolog converter? If we had Hackage
available in Prolog, then figuring out those dependencies would be no
problem at all! :-)

Take care,
Peter