haskell - Nixos configuration: `environment.systemPackages` cannot find haskellPackages -

i can find haskell packages via nix-env:

nix-enf -f "<nixpkgs>" -qap -a haskellpackages ... 

yet when try , install them using environment.systempackages in /etc/nixos/configuration.nix:

environment.systempackages = pkgs; [   haskellpackages.haskellplatform ]; 

i error:

error: attribute 'haskellplatform' missing, @ /etc/nixos/configuration.nix:54:5 

any ideas? intending on using xmonad , want haskell dev'.

haskellplatform has been removed update ghc 7.8.2, see mailing list thread more details.

you should able install package found via nix-enf -f "<nixpkgs>" -qap -a haskellpackages environment.systempackages.

searching haskellpackages.haskellplatform nix-env should result in same kind of error during rebuild:

nix-env -f "<nixpkgs>" -qap -a haskellpackages.haskellplatform error: attribute ‘haskellplatform’ in selection path ‘haskellpackages.haskellplatform’ not found 

any valid haskell package can installed in environment, example xmobar:

environment.systempackages = pkgs; [   haskellpackages.xmobar ];