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A.4.7 Wide_String Handling

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Facilities for handling strings of Wide_Character elements are found in the packages Strings.Wide_Maps, Strings.Wide_Fixed, Strings.Wide_Bounded, Strings.Wide_Unbounded, and Strings.Wide_Maps.Wide_Constants, and in the functions Strings.Wide_Hash, Strings.Wide_Fixed.Wide_Hash, Strings.Wide_Bounded.Wide_Hash, and Strings.Wide_Unbounded.Wide_Hash. They provide the same string−handling operations as the corresponding packages and functions for strings of Character elements.

Static Semantics

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The package Strings.Wide_Maps has the following declaration.

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     package Ada.Strings.Wide_Maps is
        pragma Preelaborate(Wide_Maps);

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        −− Representation for set of Wide_Character values:
        type Wide_Character_Set is private;
        pragma Preelaborable_Initialization(Wide_Character_Set);

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        Null_Set constant Wide_Character_Set;

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        type Wide_Character_Range is
          record
              Low  Wide_Character;
              High Wide_Character;
          end record;
        −− Represents Wide_Character range Low..High

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        type Wide_Character_Ranges is array (Positive range <>)
           of Wide_Character_Range;

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        function To_Set    (Ranges in Wide_Character_Ranges)
           return Wide_Character_Set;

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        function To_Set    (Span   in Wide_Character_Range)
           return Wide_Character_Set;

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        function To_Ranges (Set    in Wide_Character_Set)
           return Wide_Character_Ranges;

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

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        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;

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

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

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

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        −− Alternative representation for set of Wide_Character values:
        subtype Wide_Character_Sequence is Wide_String;

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        function To_Set (Sequence  in Wide_Character_Sequence)
           return Wide_Character_Set;

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        function To_Set (Singleton in Wide_Character)
           return Wide_Character_Set;

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        function To_Sequence (Set  in Wide_Character_Set)
           return Wide_Character_Sequence;

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        −− Representation for Wide_Character to Wide_Character mapping:
        type Wide_Character_Mapping is private;
        pragma Preelaborable_Initialization(Wide_Character_Mapping);

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        function Value (Map     in Wide_Character_Mapping;
                        Element in Wide_Character)
           return Wide_Character;

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        Identity constant Wide_Character_Mapping;

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        function To_Mapping (From, To in Wide_Character_Sequence)
           return Wide_Character_Mapping;

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        function To_Domain (Map in Wide_Character_Mapping)
           return Wide_Character_Sequence;

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        function To_Range  (Map in Wide_Character_Mapping)
           return Wide_Character_Sequence;

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        type Wide_Character_Mapping_Function is
           access function (From in Wide_Character) return Wide_Character;

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     private
        ... −− not specified by the language
     end Ada.Strings.Wide_Maps;

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The context clause for each of the packages Strings.Wide_Fixed, Strings.Wide_Bounded, and Strings.Wide_Unbounded identifies Strings.Wide_Maps instead of Strings.Maps.

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For each of the packages Strings.Fixed, Strings.Bounded, Strings.Unbounded, and Strings.Maps.Constants, and for functions Strings.Hash, Strings.Fixed.Hash, Strings.Bounded.Hash, and Strings.Unbounded.Hash, the corresponding wide string package has the same contents except that

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The following additional declaration is present in Strings.Wide_Maps.Wide_Constants:

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     Character_Set constant Wide_Maps.Wide_Character_Set;
     −−Contains each Wide_Character value WC such that
     −−Characters.Conversions.Is_Character(WC) is True

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Each Wide_Character_Set constant in the package Strings.Wide_Maps.Wide_Constants contains no values outside the Character portion of Wide_Character. Similarly, each Wide_Character_Mapping constant in this package is the identity mapping when applied to any element outside the Character portion of Wide_Character.

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Pragma Pure is replaced by pragma Preelaborate in Strings.Wide_Maps.Wide_Constants.

     NOTES

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12  If a null Wide_Character_Mapping_Function is passed to any of the Wide_String handling subprograms, Constraint_Error is propagated.

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This paragraph was deleted.