On 21.02 16:50, Simon Marlow wrote:
I lost the argument for include files, but this is why libraries cannot currently be specified inside source files. Back in the FFI discussion, we didn't have Cabal, but now that we do, Cabal is the natural place to specify these things.
Cabal is a good place, but does not handle very well optional dependencies that most programs linking against the library don't need.
I don't understand this - surely if you just put those two modules in separate packages, then everything works? Or is it that you don't want to do that?
Think about a database library supporting e.g. mysql, postgresql, sqlite and odbc. Now it needs six packages to do this: 1) foo-common for common code that does not import any of the implementations 2) foo-mysql (depends on 1) 3) foo-pgsql (depends on 1) 4) foo-sqlit (depends on 1) 5) foo-odbc (depends on 1) 6) foo (this has a connect function which uses any of the above, thus depends on 1, 2, 3, 4, 5) I don't consider this very good design and in practise this is quite tedious for the library writer. - Einar Karttunen