How can I install a Haskell library to be accessible via GHCi with Nixos?

Question

I\'ve managed to install ghc with nix-env -i ghc.

I\'d like to install a Haskell library now, how should this be done? For example the turtle (

Answer 1

As an alternative Robert's answer, one can use a nix-shell environment by creating a shell.nix file with contents of:

{ pkgs ? import  {} }:
let myGhc = pkgs.haskellPackages.ghcWithPackages (hpkgs: with hpkgs; [
      turtle
    ]);
in
pkgs.mkShell {
  buildInputs = [ myGhc ];
}

And entering this environment with nix-shell.

Alternatively this single command nix-shell -p "haskellPackages.ghcWithPackages (pkgs: [pkgs.turtle])".