Re: multiple cabal files in one directory?

On Fri, Jan 7, 2011 at 9:41 PM, wrote:

...

My use case would be the following: I have a large library, which I want to split into several cabal packages. However, I would like to keep the whole library in a single hierarchical module directory structure, so when I decide to move some module from one package to another, I only have to move a line from one .cabal file to another, and not move any files.

I would make multiple directories, each with a Cabal file and then make a symbolic link to the source directory from each of these Cabal directories. However moving a module from one package to another one is a relatively large step, that breaks other packages and thus requires increasing the major version. I find it appropriate to move files for such a change. I also tried to manage several Cabal packages in one Darcs repository, e.g. the set of data-accessor packages. But I do not like that anymore since each sub-package has its own version and this does not work well with Darcs tags and the Darcs patch comments. On Fri, 7 Jan 2011, Antoine Latter wrote:

Even if that worked in Cabal, you would run into other problems - taking a module out of a package description file doesn't stop GHC from using it during compilation if it can find it, but it does stop GHC from linking it. So you'd end up with lots of fun linker errors.

That's unfortunately true. However I have written a small script, that 'sdist's a package, unpack it in /tmp/ and try to build it with Cabal there. I run this script before uploading to Hackage in order to check for missing files. Since I use Darcs it can easily happen that Darcs registration and Cabal registration of files are out of sync. If a file is added to Darcs repository but not to Cabal description, then the Darcs test, that builds the package will succeed because of GHC's --make feature. Maybe I should put my script into a Cabal package? Or try to integrate it into cabal-install?