source("sim.sgm", "impl.sgm") // two sources
  .(                          // for each of those
    root,                     // use root
                              // as well as path to ...
    path("sw-function-spec/sw-function/
            sw-function-variants/sw-function-variant")
   )
  .                           // for each of those
                              // path down ...
   path("sw-data-dictionary-spec/sw-data-dictionaries/
            sw-data-dictionary")
  .                           // for each of those
  contents                    // return the contents