[Nix-dev] Haskell NG

[Peter Simons]

Hi Russel,

 > So please keep an eye out for long evaluation times when using
 > deepOverride as you continue your work. :)

you were right. deepOverride is too slow to be feasible for anything but
trivial cases.

The haskell-ng package set still support deepOverride, but the
recommended way to accomplish deep overrides is overrideScope

  https://github.com/NixOS/nixpkgs/commit/3c8b33eee442fd573d47555122cfe358134aeb64

which is, of course, exactly the solution you proposed in the
'haskellPackagesFixpoint' branch. Great job!

Peter