[Nix-dev] Say hello to GHC 7.7.20131202

[Peter Simons]

Yo Haskell programmers,

I've just updated ghcHEAD to a reasonably up-to-date Git snapshot, and it works
quite well. In the interest of doubling compile times for everyone trying to
use it, haskellPackages_ghcHEAD now has full shared-library support enabled by
default, so Haskell binaries come at a whopping 300KB:

 | $ nix-build -o /tmp/cabal2nix ~/.nix-defexpr -A haskellPackages_ghcHEAD.cabal2nix
 | /nix/store/7lrm31hf7lns8qbac7ciqq351gs603rr-cabal2nix-1.56
 |
 | $ ls -lh /tmp/cabal2nix/bin/cabal2nix
 | -r-xr-xr-x 1 root nixbld 360K Jan  1  1970 /tmp/cabal2nix/bin/cabal2nix

'ldd' will tell a different story, though. :-)

So, if you'd like to test your code against the upcoming 7.8 release, you can
now use Nix to do it.

Note that Hydra Central Services don't build the ghcHEAD package set. You can
pull *some* binaries for Linux/x86_64 from my server after running:

  nix-pull http://hydra.cryp.to/project/nixpkgs/channel/latest/MANIFEST

Have fun,
Peter