Ada 2005 Reference Manual

A.4.7 Wide_String Handling

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

The package Strings.Wide_Maps has the following declaration.

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

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

Null_Set : constant Wide_Character_Set;

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;

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;

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

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;

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

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

Identity : constant Wide_Character_Mapping;

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
... -- not specified by the language
end Ada.Strings.Wide_Maps;

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.

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

Wide_Space replaces Space

Wide_Character replaces Character

Wide_String replaces String

Wide_Character_Set replaces Character_Set

Wide_Character_Mapping replaces Character_Mapping

Wide_Character_Mapping_Function replaces Character_Mapping_Function

Wide_Maps replaces Maps

Bounded_Wide_String replaces Bounded_String

Null_Bounded_Wide_String replaces Null_Bounded_String

To_Bounded_Wide_String replaces To_Bounded_String

To_Wide_String replaces To_String

Set_Bounded_Wide_String replaces Set_Bounded_String

Unbounded_Wide_String replaces Unbounded_String

Null_Unbounded_Wide_String replaces Null_Unbounded_String

Wide_String_Access replaces String_Access

To_Unbounded_Wide_String replaces To_Unbounded_String

Set_Unbounded_Wide_String replaces Set_Unbounded_String

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

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

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.

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

NOTES

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

This paragraph was deleted.