Amiga ACS 1998 #4/amigaacscoverdisc1998-041998.iso/utilities/shareware/dev/ppcsmalleiffel/lib_se/client_list.e

Text File | 1998-01-16 | 3.8 KB | 159 lines

--          This file is part of SmallEiffel The GNU Eiffel Compiler.
--          Copyright (C) 1994-98 LORIA - UHP - CRIN - INRIA - FRANCE
--            Dominique COLNET and Suzanne COLLIN - [e-mail]
--                       http://www.loria.fr/SmallEiffel
-- SmallEiffel is  free  software;  you can  redistribute it and/or modify it
-- under the terms of the GNU General Public License as published by the Free
-- Software  Foundation;  either  version  2, or (at your option)  any  later
-- version. SmallEiffel is distributed in the hope that it will be useful,but
-- WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
-- or  FITNESS FOR A PARTICULAR PURPOSE.   See the GNU General Public License
-- for  more  details.  You  should  have  received a copy of the GNU General
-- Public  License  along  with  SmallEiffel;  see the file COPYING.  If not,
-- write to the  Free Software Foundation, Inc., 59 Temple Place - Suite 330,
-- Boston, MA 02111-1307, USA.
--
class CLIENT_LIST
   --
   -- To store a list of clients class like : {FOO,BAR}
   --

inherit GLOBALS;

creation {EIFFEL_PARSER,CLIENT_LIST}
   make, omitted

creation {CLIENT_LIST}
   merge

feature {NONE}

   start_position: POSITION;
     -- Of the the opening bracket when list is really written.

feature {CLIENT_LIST}

   list: CLASS_NAME_LIST;

feature {NONE}

   make(sp: like start_position; l: ARRAY[CLASS_NAME]) is
     -- When the client list is really written.
     --
     -- Note : {NONE} has the same meaning as {}.
      require
     sp /= Void;
     l /= Void implies not l.empty
      do
     start_position := sp;
     if l /= Void then
        !!list.make(l);
     end;
      ensure
     start_position = sp;
      end;

   omitted is
     -- When the client list is omitted.
     --
     -- Note : it has the same meaning as {ANY}.
      do
      end;

   merge(sp: like start_position; l1, l2: like list) is
      require
     sp /= Void
      do
     start_position := sp;
     !!list.merge(l1,l2);
      end;

feature

   is_omitted: BOOLEAN is
      do
     Result := start_position = Void;
      end;

   pretty_print is
      do
     if is_omitted then
        if fmt.zen_mode then
        else
           fmt.put_string("{ANY}");
        end
     else
        if list = Void then
           if fmt.zen_mode then
          fmt.put_string("{}");
           else
          fmt.put_string("{NONE}");
           end;
        else
           fmt.put_character('{');
           fmt.set_indent_level(2);
           list.pretty_print;
           fmt.put_character('}');
        end;
     end;
      end;

   gives_permission_to(cn: CLASS_NAME): BOOLEAN is
     -- True if the client list give permission to `cn'.
     -- When false, `eh' is preloaded with beginning of
     -- error message.
      require
     cn /= Void
      do
     if is_omitted then
        Result := true;
        -- Because it is as : {ANY}.
     elseif list = Void then
        -- Because it is as : {NONE}.
     else
        Result := list.gives_permission_to(cn);
     end;
     if not Result then
        eh.add_position(start_position);
        eh.append(cn.to_string);
        eh.append(" is not allowed to use feature.");
     end;
      end;

feature {PARENT_LIST}

   append(other: like Current): like Current is
      require
     other /= Void
      do
     if (Current = other or else
         is_omitted or else
         gives_permission_to_any)
      then
        Result := Current;
     elseif (other.is_omitted or else
         other.gives_permission_to_any)
      then
        Result := other;
     else
        !!Result.merge(start_position,list,other.list);
     end;
      end;

feature

   gives_permission_to_any: BOOLEAN is
      do
     if is_omitted then
        Result := true;
        -- Because it is as : {ANY}.
     elseif list = Void then
        -- Because it is as : {NONE}.
     else
        Result := list.gives_permission_to_any;
     end;
      end;

end -- CLIENT_LIST