needing to know install paths

[Simon Marlow]

Duncan Coutts wrote:
> On Thu, 2006-07-06 at 15:59 +0100, Duncan Coutts wrote:
> 
>>Ok, along a similar theme...
>>
>>We provide the Paths_${projname}.hs module, as a little extra there it
>>provides the current version number. Perhaps we could generalise that
>>and provide the whole cabal file (using the normal Cabal types).
> 
> 
> More monologue...
> 
> Actually perhaps this isn't such a good idea. It'd tie the version of
> cabal more strongly to the app it's installing.
> 
> Suppose we generate a module using the current version of cabal that's
> building the package. That has to be the same version as the program
> gets built against if it's to use this generated module. And then that
> has to be sufficiently close to the version that the packages was
> designed to use so that the fields from the cabal package description
> are the same.

[ catching up on cabal-devel... ]

Actually when I first added the Paths_<pkg> support I did try including the 
whole PackageDescription in that file.  However I backed off precisely because 
of the reason you give: it means every package effectively includes a dependency 
on Cabal, and the package must therefore say which version of Cabal it is expecting.

Cheers,
	Simon