Package Name: ada.strings.wide_maps

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------------------------------------------------------------------------------
--                                                                          --
--                         GNAT RUNTIME COMPONENTS                          --
--                                                                          --
--                A D A . S T R I N G S . W I D E _ M A P S                 --
--                                                                          --
--                                 S p e c                                  --
--                                                                          --
--                            $Revision: 1.9 $                              --
--                                                                          --
-- This specification is adapted from the Ada Reference Manual for use with --
-- GNAT.  In accordance with the copyright of that document, you can freely --
-- copy and modify this specification,  provided that if you redistribute a --
-- modified version,  any changes that you have made are clearly indicated. --
--                                                                          --

------------------------------------------------------------------------------

with Ada.Finalization;
package Ada.Strings.Wide_Maps is

   pragma Preelaborate (Wide_Maps);
   -------------------------------------
   -- Wide Character Set Declarations --

   -------------------------------------
   type Wide_Character_Set is private;

   --  Representation for a set of Wide_Character values:

   Null_Set : constant Wide_Character_Set;
   ------------------------------------------
   -- Constructors for Wide Character Sets --

   ------------------------------------------
   type Wide_Character_Range is record
      Low  : Wide_Character;
      High : Wide_Character;
   end record;

   --  Represents Wide_Character range Low .. High
   type Wide_Character_Ranges is

     array (Positive range <>) of Wide_Character_Range;
   function To_Set
     (Ranges : in Wide_Character_Ranges)

      return   Wide_Character_Set;
   function To_Set
     (Span : in Wide_Character_Range)

      return Wide_Character_Set;
   function To_Ranges
     (Set :  in Wide_Character_Set)

      return Wide_Character_Ranges;
   ---------------------------------------
   -- Operations on Wide Character Sets --

   ---------------------------------------

   function "=" (Left, Right : in Wide_Character_Set) return Boolean;
   function "not"
     (Right  : in Wide_Character_Set)

      return Wide_Character_Set;
   function "and"
     (Left, Right : in Wide_Character_Set)

      return        Wide_Character_Set;
   function "or"
     (Left, Right : in Wide_Character_Set)

      return        Wide_Character_Set;
   function "xor"
     (Left, Right : in Wide_Character_Set)

      return        Wide_Character_Set;
   function "-"
     (Left, Right : in Wide_Character_Set)

      return        Wide_Character_Set;
   function Is_In
     (Element : in Wide_Character;
      Set     : in Wide_Character_Set)

      return    Boolean;
   function Is_Subset
     (Elements : in Wide_Character_Set;
      Set      : in Wide_Character_Set)

      return     Boolean;
   function "<="
     (Left  : in Wide_Character_Set;
      Right : in Wide_Character_Set)
      return  Boolean

   renames Is_Subset;
   subtype Wide_Character_Sequence is Wide_String;

   --  Alternative representation for a set of character values
   function To_Set
     (Sequence  : in Wide_Character_Sequence)

      return      Wide_Character_Set;
   function To_Set
     (Singleton : in Wide_Character)

      return      Wide_Character_Set;
   function To_Sequence
     (Set  : in Wide_Character_Set)

      return Wide_Character_Sequence;
   -----------------------------------------
   -- Wide Character Mapping Declarations --

   -----------------------------------------
   type Wide_Character_Mapping is private;

   --  Representation for a wide character to wide character mapping:
   function Value
     (Map     : in Wide_Character_Mapping;
      Element : in Wide_Character)

      return    Wide_Character;

   Identity : constant Wide_Character_Mapping;
   ---------------------------------
   -- Operations on Wide Mappings --

   ---------------------------------
   function To_Mapping
     (From, To : in Wide_Character_Sequence)

      return     Wide_Character_Mapping;
   function To_Domain
     (Map  : in Wide_Character_Mapping)

      return Wide_Character_Sequence;
   function To_Range
     (Map  : in Wide_Character_Mapping)

      return Wide_Character_Sequence;
   type Wide_Character_Mapping_Function is

      access function (From : in Wide_Character) return Wide_Character;
private

   package AF renames Ada.Finalization;
   ------------------------------------------
   -- Representation of Wide_Character_Set --

   ------------------------------------------
   --  A wide character set is represented as a sequence of wide character
   --  ranges (i.e. an object of type Wide_Character_Ranges) in which the

   --  following hold:
   --    The lower bound is 1
   --    The ranges are in order by increasing Low values

   --    The ranges are non-overlapping and discontigous
   --  A character value is in the set if it is contained in one of the
   --  ranges. The actual Wide_Character_Set value is a controlled pointer
   --  to this Wide_Character_Ranges value. The use of a controlled type

   --  is necessary to prevent storage leaks.

   type Wide_Character_Ranges_Access is access all Wide_Character_Ranges;
   type Wide_Character_Set is new AF.Controlled with record
      Set : Wide_Character_Ranges_Access;

   end record;
   procedure Initialize (Object : in out Wide_Character_Set);
   procedure Adjust     (Object : in out Wide_Character_Set);

   procedure Finalize   (Object : in out Wide_Character_Set);
   Null_Range : aliased constant Wide_Character_Ranges :=

                  (1 .. 0 => (Low => ' ', High => ' '));
   Null_Set : constant Wide_Character_Set :=
                (AF.Controlled with

                 Set => Null_Range'Unrestricted_Access);
   ----------------------------------------------
   -- Representation of Wide_Character_Mapping --

   ----------------------------------------------
   --  A wide character mapping is represented as two strings of equal
   --  length, where any character appearing in Domain is mapped to the
   --  corresponding character in Rangev. A character not appearing in
   --  Domain is mapped to itself. The characters in Domain are sorted

   --  in ascending order.
   --  The actual Wide_Character_Mapping value is a controlled record
   --  that contains a pointer to a discriminated record containing the

   --  range and domain values.
   --  Note: this representation is canonical, and the values stored in
   --  Domain and Rangev are exactly the values that are returned by the
   --  functions To_Domain and To_Range. The use of a controlled type is

   --  necessary to prevent storage leaks.
   type Wide_Character_Mapping_Values (Length : Natural) is record
      Domain : Wide_Character_Sequence (1 .. Length);
      Rangev : Wide_Character_Sequence (1 .. Length);

   end record;
   type Wide_Character_Mapping_Values_Access is

     access all Wide_Character_Mapping_Values;
   type Wide_Character_Mapping is new AF.Controlled with record
      Map : Wide_Character_Mapping_Values_Access;

   end record;
   procedure Initialize (Object : in out Wide_Character_Mapping);
   procedure Adjust     (Object : in out Wide_Character_Mapping);

   procedure Finalize   (Object : in out Wide_Character_Mapping);
   Null_Map : aliased constant Wide_Character_Mapping_Values :=
                 (Length => 0,
                  Domain => "",

                  Rangev => "");
   Identity : constant Wide_Character_Mapping :=
                (AF.Controlled with

                 Map => Null_Map'Unrestricted_Access);
end Ada.Strings.Wide_Maps;