package descriptions

[ross at soi.city.ac.uk]

On Wed, Jan 05, 2005 at 01:08:51PM -0000, Simon Marlow wrote:
> Looks ok.  A couple of things worry me slightly (I think these were
> problems before, but your description has highlighted them):
> 
>  - if the package and executables can have different hs-source-dirs
>    and yet share modules, how does this work?  Is it sensible?
> 
>  - since the package and each executable can specify different extensions
>    and options, this means in principle we have to compile each module
>    multiple times - it's not safe to re-use the compiled version in
>    the package and executables unless the compiler options are identical.
>    That means not just options-ghc, but also cc-options, includes,
>    and include-dirs.

I agree it's a problem, but I think I think it's just between the
executables (i.e. the executables should be restricted to the public
interface of the library, if any).  I'd been assuming that the auxiliary
modules used by executables inhabited a common namespace (and this is
a common usage pattern), but the varying options do conflict with this.