src/Pure/PIDE/resources.scala

         val text = Symbol.decode(Scan.reader_decode_utf8(is_utf8, raw_text))
         val spans = syntax.parse_spans(text)
         val dir = Path.explode(name.master_dir)
         (for {
           span <- spans.iterator
-          file <- span.loaded_files(syntax)._1
+          file <- span.loaded_files(syntax).files
         } yield (dir + Path.explode(file)).expand).toList
       }
       else Nil
     }
   }