In Nix flakes, inputs must be written as pure data, without functions or thunks
(see issues NixOS/nix#3966
and NixOS/nix#4945).
To generate inputs with the full power of the Nix language,
one can create a template file, e.g. flake.in.nix and generate the
flake.nix by evaluating and pretty-printing the inputs attribute.
This flake is a convenience wrapper around that.
To start using this, run
nix flake init -t github:jorsn/flakegen
This will create the files flake.nix and flake.in.nix.
It will not overwrite existing files.
After editing flake.in.nix as you like, run
nix run .#genflake flake.nix
to update the flake.nix.
To preview the new flake.nix without replacing it, run the following:
nix run .#genflake
You can repair a broken flake.nix by
deleting flake.nix and running
nix flake init -t github:jorsn/flakegen
nix run .#genflake flake.nix
as long as flake.in.nix works.