Package Name: ada.finalization.list_controller

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------------------------------------------------------------------------------
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--                         GNAT COMPILER COMPONENTS                         --
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------------------------------------------------------------------------------
with System.Finalization_Root;

package Ada.Finalization.List_Controller is

   package SFR renames System.Finalization_Root;
   ----------------------------
   -- Simple_List_Controller --

   ----------------------------
   type Simple_List_Controller is new Ada.Finalization.Limited_Controlled
     with record
        F : SFR.Finalizable_Ptr;
     end record;
      --  Used by the compiler to carry a list of temporary objects that
      --  needs to be finalized after having being used. This list is
      --  embedded in a controlled type so that if an exception is raised
      --  while those temporaries are still in use, they will be reclaimed

      --  by the normal finalization mechanism.

   procedure Finalize (Object : in out Simple_List_Controller);
   ---------------------
   -- List_Controller --

   ---------------------
   --  Management of a bidirectional linked heterogenous list of
   --  dynamically Allocated objects. To simplify the management of the
   --  linked list, the First and Last elements are statically part of the
   --  original List controller:
   --
   --        +------------+
   --        |          --|-->--
   --        +------------+
   --        |--<--       |                      record with ctrl components
   --        |------------|                         +----------+
   --     +--|--   L      |                         |          |
   --     |  |------------|                         |          |
   --     |  |+--------+  |       +--------+        |+--------+|
   --     +->||  prev  | F|---<---|--      |----<---||--      ||--<--+
   --        ||--------| i|       |--------|        ||--------||     |
   --        || next   | r|--->---|      --|---->---||      --||--------+
   --        |+--------+ s|       |--------|        ||--------||     |  |
   --        |           t|       | ctrl   |        ||        ||     |  |
   --        |            |       :        :        |+--------+|     |  |
   --        |            |       : object :        |rec       |     |  |
   --        |            |       :        :        |controller|     |  |
   --        |            |       |        |        |          |     |  v
   --        |+--------+  |       +--------+        +----------+     |  |
   --        ||  prev -|-L|--------------------->--------------------+  |
   --        ||--------| a|                                             |
   --        || next   | s|-------------------<-------------------------+
   --        |+--------+ t|
   --        |            |

   --        +------------+
   type List_Controller is new Ada.Finalization.Limited_Controlled
     with record
        F    :  SFR.Finalizable_Ptr;
        First,
        Last : aliased SFR.Root_Controlled;
     end record;
   --  Controls the chains of dynamically allocated controlled
   --  objects makes sure that they get finalized upon exit from

   --  the access type that defined them
   procedure Initialize (Object : in out List_Controller);

   procedure Finalize   (Object : in out List_Controller);
end Ada.Finalization.List_Controller;