Basic nix-shell config for testing flakes

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1

I’m trying to follow this tutorial example of using flakes with nix-shell.

My shell.nix file.

{ pkgs ? import <nixpkgs> {}}:
        pkgs.mkSell {
          name = "MyAswsomeShell";
          extraOptions = "experimental features = nix-command flakes";
          buildIputs - with pkgs; 
            nixFlakes
          ];

          shellHook = ""
            echo "Welcome to my awesome shell";
          ""
        }

When I attempt to run ‘nix flake init’, I get

error: experimental Nix feature 'nix-command' is disabled; use '--extra-experimental-features nix-command' to override

I suspect that I’m missing something in the shell.nix in order to get ‘nix-command’ feature enable.

The following didn’t work either

nix-shell ----extra-experimental-features nix-command

Thanks.

2

This version works here:

{ pkgs ? import <nixpkgs> {}}:
        pkgs.mkShell {
          name = "MyAswsomeShell";
          extraOptions = ''
	  --experimental-features = "nix-command flakes"
	  '';
          buildIputs = with pkgs; [ 
            nixFlakes
          ];

          shellHook = ''
            echo "Welcome to my awesome shell";
          '';
        }