-- This file is part of Liberty Eiffel.
--
-- Liberty Eiffel 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, version 3 of the License.
--
-- Liberty Eiffel 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 Liberty Eiffel.  If not, see <http://www.gnu.org/licenses/>.
--
deferred class LIBERTY_INTERPRETER_OBJECT_NATIVE[E_]

inherit
   LIBERTY_INTERPRETER_OBJECT

feature {ANY}
   type: LIBERTY_ACTUAL_TYPE

   is_equal (other: LIBERTY_INTERPRETER_OBJECT): BOOLEAN is
      local
         o: like Current
      do
         if other.is_void then
            -- Obviously this object is not Void.
         else
            o ::= other
            Result := item = o.item
         end
      end

   item: E_

   set_item (a_item: like item) is
      do
         item := a_item
      ensure
         item = a_item
      end

feature {LIBERTY_INTERPRETER_EXTERNAL_TYPE_ANY_BUILTINS} -- Standard builtings
   builtin_is_equal (other: LIBERTY_INTERPRETER_OBJECT; a_position: LIBERTY_POSITION): BOOLEAN is
      local
         o: like Current
      do
         if type = other.type then
            o ::= other
            Result := item.is_equal(o.item)
         else
            interpreter.fatal_error("Type mismatch: expected " + type.full_name + ", but got " + other.type.full_name, a_position)
         end
      end

   builtin_standard_is_equal (other: LIBERTY_INTERPRETER_OBJECT; a_position: LIBERTY_POSITION): BOOLEAN is
      local
         o: like Current
      do
         if type = other.type then
            o ::= other
            Result := item.is_equal(o.item)
         else
            interpreter.fatal_error("Type mismatch: expected " + type.full_name + ", but got " + other.type.full_name, a_position)
         end
      end

   builtin_copy (other: LIBERTY_INTERPRETER_OBJECT; a_position: LIBERTY_POSITION) is
      local
         o: like Current
      do
         if type = other.type then
            o ::= other
            item := o.item
         else
            interpreter.fatal_error("Type mismatch: expected " + type.full_name + ", but got " + other.type.full_name, a_position)
         end
      end

   builtin_twin (a_position: LIBERTY_POSITION): like Current is
      do
         Result := as_right_value
      end

   builtin_standard_copy (other: LIBERTY_INTERPRETER_OBJECT; a_position: LIBERTY_POSITION) is
      local
         o: like Current
      do
         if type = other.type then
            o ::= other
            item := o.item
         else
            interpreter.fatal_error("Type mismatch: expected " + type.full_name + ", but got " + other.type.full_name, a_position)
         end
      end

   builtin_standard_twin (a_position: LIBERTY_POSITION): like Current is
      do
         Result := as_right_value
      end

feature {LIBERTY_INTERPRETER_OBJECT}
   do_deep_twin (deep_twin_memory: DICTIONARY[LIBERTY_INTERPRETER_OBJECT, LIBERTY_INTERPRETER_OBJECT]; a_position: LIBERTY_POSITION): LIBERTY_INTERPRETER_OBJECT is
      do
         Result := as_right_value
      end

   do_deep_equal (other: LIBERTY_INTERPRETER_OBJECT; deep_equal_memory: SET[LIBERTY_INTERPRETER_OBJECT]; a_position: LIBERTY_POSITION): BOOLEAN is
      local
         o: like Current
      do
         if type = other.type then
            o ::= other
            Result := item.is_equal(o.item)
         else
            interpreter.fatal_error("Type mismatch: expected " + type.full_name + ", but got " + other.type.full_name, a_position)
         end
      end

feature {LIBERTY_INTERPRETER_OBJECT_PRINTER, LIBERTY_INTERPRETER_FEATURE_CALL}
   show_stack (o: OUTPUT_STREAM; indent: INTEGER) is
      do
         item.print_on(o)
         o.put_new_line
      end

feature {}
   make (a_interpreter: like interpreter; a_type: like type; a_position: like position) is
      require
         a_interpreter /= Void
         a_type /= Void
         a_position /= Void
      do
         interpreter := a_interpreter
         type := a_type
         position := a_position
      ensure
         interpreter = a_interpreter
         type = a_type
         position = a_position
      end

   with_item (a_interpreter: like interpreter; a_type: like type; a_item: like item; a_position: like position) is
      require
         a_interpreter /= Void
         a_type /= Void
         a_position /= Void
      do
         make(a_interpreter, a_type, a_position)
         item := a_item
      ensure
         interpreter = a_interpreter
         type = a_type
         item = a_item
         position = a_position
      end

invariant
   item_is_expanded: item /= Void

end -- class LIBERTY_INTERPRETER_OBJECT_NATIVE