Failed to switch to flake in virtualbox envrionment

[fabilong]

newbie here and would appreciate it if anybody could explain this to me

error is

cannot lookup '<nixpkgs/nixos/modules/installer/virtualbox-demo.nix>' in pure evaluation mode ( use '--impure' to override)

[ryan4yin]

<xxx> is a nix lookup path, as Lookup paths - nix.dev said:

While you will encounter many such examples, we recommend to avoid lookup paths in production code, as they are impurities which are not reproducible.

That's to say, lookup paths are impurities, and flake are pure by default, so flake will not accept it.

As the error suggest, you can add --impure at the end of your nix command to avoid this error.

A better solution is to switch to modulePaths - A parameter available only in NixOS, which is a path pointing to nixpkgs/nixos/modules. An example: hardware-configuration.nix

[fabilong]

thanks

Ryan Yin @.***>于2024年6月24日 周一上午9:07写道：

is a nix lookup path, as Lookup paths - nix.dev said: While you will encounter many such examples, we recommend to avoid lookup paths in production code, as they are impurities which are not reproducible. That's to say, lookup paths are impurities, and flake are pure by default, so flake will not accept it. As the error suggest, you can add --impure at the end of your nix command to avoid this error. A better solution is to switch to modulePaths - A parameter available only in NixOS, which is a path pointing to nixpkgs/nixos/modules . An example: hardware-configuration.nix — Reply to this email directly, view it on GitHub , or unsubscribe . You are receiving this because you authored the thread.Message ID: ***@***.***>