Hi Xyne,
"haskell-foo" would contain foo 1.4, foo 1.5 and whatever other versions of foo that one could reasonably expect.
the idea is intriguing. This kind of setup means, though, that when a new version foo 1.6 comes out, re-building haskell-foo consists of builds of foo 1.4, 1.5, and 1.6 -- because all these versions are contained in the package. Assuming that all libraries are built in variants for profiling and shared linking, then "foo" must be compiled a whopping 12 times to build that package. Also, it means that users download the same code over and over again with every update, because haskell-foo 1.6 contains exactly those copies of foo 1.4 and 1.5 that they've already installed. It's not a particularly efficient solution, but as far as I can tell, it would get the job done. Take care, Peter