Nix shell: How to list the installed Haskell package versions
haskell, nix
Solution
You can try to `nix-store -q --references $out` after you entered the shell. This will, however, mix both haskell and non-haskell dependencies in output.
This is a complete example with filter applied:
` $ nix-store -q --references $out \ | while read p; do du -a $p | grep -q ghc && echo $p; done `
Problem
As a non-nix'er I installed the newest version of https://github.com/reflex-frp/reflex-platform. I think working in this nix-shell is a nice experience. Now I want to know which Haskell packages in which versions are installed and used in this shell. After some googling I found a nix-env command in the following form: `nix-env -f '<nixpkgs>' -qaPA haskellPackages|grep reflex-dom` This command gives me the version of reflex-dom as reflex-dom-0.3. But I know from here that in my nix shell I use the newest version 0.4 of reflex-dom. So I assume the above command just lists the available Hackage packages. What is the correct nix-env -q command to get only the installed Haskell packages and its versions?. (I played with the --installed option, however I never got something back)