[Haskell-cafe] hackage dependencies for cabal setup scripts

[Antoine Latter]

On Wed, Dec 8, 2010 at 11:12 AM, Duncan Coutts
<duncan.coutts at googlemail.com> wrote:
> On 8 December 2010 17:02, Sönke Hahn <shahn at cs.tu-berlin.de> wrote:
>> Hi!
>>
>> If you write a cabal setup script with user hooks, is there a way to tell
>> cabal-install that the setup script itself depends on some package from
>> hackage? (The dependency would be cabal-macosx in my case.)
>
> No, the Cabal spec has no support for that. It is assumed that
> Setup.hs scripts have minimal dependencies, since the original idea
> was that these would be the first user interface, so they must
> compile.
>
> My plan is to move away from Setup.hs being the primary user interface
> and that would in principle make it possible for Setup.hs scripts to
> have other dependencies, however we will need to extend the Cabal
> specification and .cabal format to enable it.
>

As long as we're wishing, it would be nice if I could write tools
which rely on a particular package's userHooks without having to have
my utility be a part of the Cabal library.

I'm not sure what that would look like - it would almost require
packages conforming to the "simple" install mechanism would expose a
library that custom tools (and Setup.hs?) could load, which sounds
fraught with peril.

Antoine