[Nix-dev] Haskell updates (was: [nixpkgs] Fix haddock building for unicode packages (#864))

[Peter Simons]

The changes are now in master, too:

commit d64917ad17277b8e16893ee31533ec2e33446fa7
Author: Peter Simons <simons at cryp.to>
Date:   Sat Oct 26 18:33:09 2013 +0200

    Back-port Haskell-related improvements from stdenv-updates.
    
     * There now is full support for building Haskell packages as shared libraries
       for GHC versions 7.4.2 or later. The Cabal builder recognizes the following
       attributes:
    
        - enableSharedLibraries configures Cabal to build of shared libraries in
          addition to static ones. This option requires that all dependencies of
          the package have been compiled for use in shared libraries, too.
    
        - enableSharedExecutables configures Cabal to prefer shared libraries when
          linking executables.
    
       The default values for these attributes are arguments to the haskellPackages
       expression.
    
     * Haskell builds now run in a LANG="en_US.UTF-8" environment to avoid plenty
       of build and test suite errors. Without this setting, GHC seems unable to
       deal with the UTF-8 character encoding that's generally considered standard
       in the Haskell world.
    
     * The Cabal builder supports a new attribute 'testTarget' to specify the exact
       set of tests to be run during the check phase.
    
     * The ghc-wrapper attribute ghcVersion has been removed. Instead, we use the
       ghc.version attribute, which exists in unwrapped GHC derivations, too.

Peter