Show new nix cli commands when profile is not used

[Gerschtli]

Hey, in my environment I don't use nix-env or nix profile at all. Also I don't use channels so I would like to see the new nix cli commands with the nixpkgs registry name instead.

What do you think about an environment variable, a config value, or a dedicated nix package for new nix cli/flakes commands only?

[Niols]

I feel there are two requests in this issue:

1. Be able to customize whether or not to show the nix-env or nix profile part of the help.
2. Be able to customize whether to show nix-env/nix-shell hints or nix profile/nix run ones instead of relying on the script guessing from the filesystem.

Is that right? Personally, just like @Gerschtli, I'd got for no nix-env/nix profile part of the help, and only the nix run one, but it's probably not much harder to offer the choice!

[srid]

FWIW, the new cli commands are displayed if the user profile manifest exists. See https://nixos.zulipchat.com/#narrow/stream/413950-nix/topic/nix-index/near/416719968