{
  foo = (
    (
      (
        92
      )
    )
  );
  xxx = listToAttrs (concatMap (name:
    let a = 4; in 5
  ));
  foldAttrs = op: nul: list_of_attrs:
    fold
      (n: a:
        fold
          (name: o:
            o // { ${name} = op n.${name} (a.${name} or nul); }
          )
          a
          (attrNames n)
      )
      { }
      list_of_attrs;
  bar = fun "arg" (callPackage ./. {
    inherit foo;
  });
}