On 08.08 01:45, Brian Smith wrote:
Let's say we have multiple versions of a package installed: a-1.0 a-1.0.1 a-1.1 a-2.0 and that we have the following Build-Depends in a package description: Build-Depends: a >= 1.0
Now, when I configure, Cabal will choose a-2.0 as the package to build with. However, it makes more sense to choose a-1.0 by default instead.
This behaviour would make upgrading packages quite painful. Lets suppose we have packages A, B and C, with both A and B depending on C. If we have A, B and C 1.0 installed and wish to upgrade to C-2.0 we can currently install C-2.0 and reinstall A and B (they automatically depend on the new C) and later remove A. With using the minimum version we would need to suply something like --enable-max-library-versions when reinstalling packages or alternatively first remove A making the installation broken until new A, B and C have been installed. I think that most often people have old versions of a package because some particular package depends on that and they want to use the new version when possible. - Einar Karttunen