[Gtk2hs-devel] move Gtk2HsSetup.hs to gtk2hs-buildtools

[Duncan Coutts]

On Thu, 2010-11-25 at 11:16 +0100, Axel Simon wrote:
> Dear Libraries,
> 
> this message is on shortcomings of cabal with respect to automatically  
> installing the gtk package which (a) depends on a package that  
> contains only build tools (i.e. only binaries) and (b) has a big  
> custom Haskell file Gtk2HsSetup.hs that Setup.hs has to import (and  
> which is required in any package in the Gtk2Hs suite). This file is  
> copied into every package of the Gtk2Hs suite which is a pain to  
> maintain.

I don't have any easy answers.

The "right solution" for (a) is for cabal-install to track build tools
(and C libs and all other dependencies, not just Haskell libs).

For dependencies of Setup.hs, this is also hard. The original Cabal spec
envisioned Setup.hs scripts being self-contained having no deps other
than the base libs and Cabal itself, since this was intended as the
primary user interface, so it must compile without a lot of fuss. In
principle for some future Cabal spec revision we could add some way to
declare that the build system itself requires certain dependencies.

I also hope that the size of the Gtk2Hs Setup.hs can eventually be
reduced by supporting c2hs in Cabal properly (i.e. including .chs
dependencies).

Duncan