Extending Cabal

[Krasimir Angelov]

Hello Guys,

I have started to extend Cabal with new feature. What I need is to
have multiple Haskell source directories for one package. This feature
is not substantial if you are packaging library, since it is supposed
to have hierarchical namespace, but it is useful if you have
executable. It is not mandatory to have hierarchical namespace for
executables but if you are using flat namespace then with Cabal you
will be restricted to keep all your source files in single directory.
The extension that I have in mind will allow to break this
restriction. GHC source tree is a good example of such type of
project. It uses flat namespace but its source files are separated in
multiple directories. The only visible change that is required is to
replace hs-source-dir field to hs-source-dirs where the latter will
accept a list of directories. The parser can still accept
hs-source-dir for backward compatibility. I would like to hear any
suggestions or objections against this extensions. I don't want to
waste my time if this extension will not be accepted.

Cheers,
  Krasimir