#! @ENV_PROG@ nix-shell
#! nix-shell "{ script, path, ... }: assert path == ./shell.nix; script { fooContents = toString ./.; }"
#! nix-shell --no-substitute
#! nix-shell --expr
#! nix-shell --arg script "import ((builtins.getEnv ''TEST_ROOT'')+''/shell.nix'')"
#! nix-shell --arg path "./shell.nix"
#! nix-shell -A shellDrv
#! nix-shell -i bash
#! nix-shell --option nix-shell-shebang-arguments-relative-to-script false
echo "$FOO"