package foo:foo;

world foo {
  import foo: func();
  import bar: func(arg: u32);
  import some-interface: interface {
  }

  export foo2: func();
  export bar2: func() -> u32;
  export another-interface: interface {
  }
}
world just-import {
  import foo: func();
}
world just-export {
  export foo: func();
}