Mutually recursive modules
I would like to have mutually recursive modules, without creating special files. In my experience, some types(for example) are naturally mutually recursive. As someone said on the mailing lists:
You can *program* in Haskell and you can program *in Haskell*. In short, the user should concentrate on writing the program and not on artificial complexities imposed on by the implementation.
Mutually recursive modules are a solved problem, since there are other systems that can do this. They might have a cost associated with them, but I cannot imagine it to be significant in any interesting program.
Since mutually recursive modules are already in Haskell98, any user should be able to expect that the "most popular" compiler for Haskell fully supports them. It's 2007, not 1998.