anchor.diff:            name             :: '_' | app_name(),
             is_escript       :: '_' | boolean() | {inlined, escript_app_name()},
             use_selected_vsn :: '_' | vsn | dir | undefined,
  -          active_dir       :: '_' | dir(),
  +          active_dir       :: '_' | dir() | undefined,
             sorted_dirs      :: '_' | [dir()],
  -          vsn              :: '_' | app_vsn(),
  -          label            :: '_' | app_label(),
  +          vsn              :: '_' | app_vsn() | undefined,
  +          label            :: '_' | app_label() | undefined,
             info             :: '_' | #app_info{} | undefined,
             mods             :: '_' | [#mod{}],
   
  
positive.code:           rels     	       :: [#rel{}],
            emu_name 	       :: emu_name(),
            profile  	       :: profile(),
  	  excl_lib             :: excl_lib(),
            incl_sys_filters     :: [#regexp{}],
            excl_sys_filters     :: [#regexp{}],
            incl_app_filters     :: [#regexp{}],
  
negative.code:           debug_info            :: '_' | debug_info() | undefined,
            app_file              :: '_' | app_file() | undefined,
            app_type              :: '_' | app_type() | undefined,
            incl_app_filters      :: '_' | [#regexp{}] | undefined,
            excl_app_filters      :: '_' | [#regexp{}] | undefined,
            incl_archive_filters  :: '_' | [#regexp{}] | undefined,
            excl_archive_filters  :: '_' | [#regexp{}] | undefined,
            archive_opts          :: '_' | [archive_opt()] | undefined,
  
            %% Dynamic
            status          :: '_' | status(),
            uses_mods       :: '_' | [mod_name()] | undefined,
            used_by_mods    :: '_' | [mod_name()] | undefined,
            uses_apps       :: '_' | [app_name()] | undefined,
            used_by_apps    :: '_' | [app_name()] | undefined,
            is_pre_included :: '_' | '$2' | boolean() | undefined,
            is_included     :: '_' | '$1' | boolean() | undefined,
            rels            :: '_' | [rel_name()] | undefined
  	}).
  
  -record(rel_app,
  