A.3.5 The Package Wide_Characters.Handling
The package Wide_Characters.Handling provides operations 
for classifying Wide_Characters and case folding for Wide_Characters. 
Static Semantics
The library package 
Wide_Characters.Handling has the following declaration:
package Ada.Wide_Characters.Handling 
is
   pragma Pure(Handling);
 
   function Character_Set_Version 
return String;
 
   function Is_Control (Item : Wide_Character) 
return Boolean;
 
   function Is_Letter (Item : Wide_Character) 
return Boolean;
 
   function Is_Lower (Item : Wide_Character) 
return Boolean;
 
   function Is_Upper (Item : Wide_Character) 
return Boolean;
 
   function Is_Digit (Item : Wide_Character) 
return Boolean;
 
   function Is_Decimal_Digit (Item : Wide_Character) 
return Boolean
      
renames Is_Digit;
 
   function Is_Hexadecimal_Digit (Item : Wide_Character) 
return Boolean;
 
   function Is_Alphanumeric (Item : Wide_Character) 
return Boolean;
 
   function Is_Special (Item : Wide_Character) 
return Boolean;
 
   function Is_Line_Terminator (Item : Wide_Character) 
return Boolean;
 
   function Is_Mark (Item : Wide_Character) 
return Boolean;
 
   function Is_Other_Format (Item : Wide_Character) 
return Boolean;
 
   function Is_Punctuation_Connector (Item : Wide_Character) 
return Boolean;
 
   function Is_Space (Item : Wide_Character) 
return Boolean;
 
   function Is_Graphic (Item : Wide_Character) 
return Boolean;
 
   function To_Lower (Item : Wide_Character) 
return Wide_Character;
   
function To_Upper (Item : Wide_Character) 
return Wide_Character;
 
   function To_Lower (Item : Wide_String) 
return Wide_String;
   
function To_Upper (Item : Wide_String) 
return Wide_String;
 
end Ada.Wide_Characters.Handling;
 The subprograms defined in Wide_Characters.Handling 
are locale independent.
function Character_Set_Version return String;
Returns an implementation-defined 
identifier that identifies the version of the character set standard 
that is used for categorizing characters by the implementation.
function Is_Control (Item : Wide_Character) return Boolean;
Returns True if 
the Wide_Character designated by Item is categorized as other_control; 
otherwise returns False.
function Is_Letter (Item : Wide_Character) return Boolean;
Returns True if 
the Wide_Character designated by Item is categorized as letter_uppercase, 
letter_lowercase, letter_titlecase, 
letter_modifier, letter_other, 
or number_letter; otherwise returns False.
function Is_Lower (Item : Wide_Character) return Boolean;
Returns True if 
the Wide_Character designated by Item is categorized as letter_lowercase; 
otherwise returns False.
function Is_Upper (Item : Wide_Character) return Boolean;
Returns True if 
the Wide_Character designated by Item is categorized as letter_uppercase; 
otherwise returns False.
function Is_Digit (Item : Wide_Character) return Boolean;
Returns True if 
the Wide_Character designated by Item is categorized as number_decimal; 
otherwise returns False.
function Is_Hexadecimal_Digit (Item : Wide_Character) return Boolean;
Returns True if 
the Wide_Character designated by Item is categorized as number_decimal, 
or is in the range 'A' .. 'F' or 'a' .. 'f'; otherwise returns False.
function Is_Alphanumeric (Item : Wide_Character) return Boolean;
Returns True if 
the Wide_Character designated by Item is categorized as letter_uppercase, 
letter_lowercase, letter_titlecase, 
letter_modifier, letter_other, 
number_letter, or number_decimal; 
otherwise returns False.
function Is_Special (Item : Wide_Character) return Boolean;
Returns True if 
the Wide_Character designated by Item is categorized as graphic_character, 
but not categorized as letter_uppercase, letter_lowercase, 
letter_titlecase, letter_modifier, 
letter_other, number_letter, 
or number_decimal; otherwise returns False.
function Is_Line_Terminator (Item : Wide_Character) return Boolean;
Returns True if 
the Wide_Character designated by Item is categorized as separator_line 
or separator_paragraph, or if Item is a conventional 
line terminator character (Line_Feed, Line_Tabulation, Form_Feed, Carriage_Return, 
Next_Line); otherwise returns False.
function Is_Mark (Item : Wide_Character) return Boolean;
Returns True if 
the Wide_Character designated by Item is categorized as mark_non_spacing 
or mark_spacing_combining; otherwise returns 
False.
function Is_Other_Format (Item : Wide_Character) return Boolean;
Returns True if 
the Wide_Character designated by Item is categorized as other_format; 
otherwise returns False.
function Is_Punctuation_Connector (Item : Wide_Character) return Boolean;
Returns True if 
the Wide_Character designated by Item is categorized as punctuation_connector; 
otherwise returns False.
function Is_Space (Item : Wide_Character) return Boolean;
Returns True if 
the Wide_Character designated by Item is categorized as separator_space; 
otherwise returns False.
function Is_Graphic (Item : Wide_Character) return Boolean;
Returns True if 
the Wide_Character designated by Item is categorized as graphic_character; 
otherwise returns False.
function To_Lower (Item : Wide_Character) return Wide_Character;
Returns the Simple 
Lowercase Mapping as defined by documents referenced in the note in Clause 
1 of ISO/IEC 10646:2011 of the Wide_Character designated by Item. If 
the Simple Lowercase Mapping does not exist for the Wide_Character designated 
by Item, then the value of Item is returned.
function To_Lower (Item : Wide_String) return Wide_String;
Returns the result 
of applying the To_Lower conversion to each Wide_Character element of 
the Wide_String designated by Item. The result is the null Wide_String 
if the value of the formal parameter is the null Wide_String. The lower 
bound of the result Wide_String is 1.
function To_Upper (Item : Wide_Character) return Wide_Character;
Returns the Simple 
Uppercase Mapping as defined by documents referenced in the note in Clause 
1 of ISO/IEC 10646:2011 of the Wide_Character designated by Item. If 
the Simple Uppercase Mapping does not exist for the Wide_Character designated 
by Item, then the value of Item is returned.
function To_Upper (Item : Wide_String) return Wide_String;
Returns the result 
of applying the To_Upper conversion to each Wide_Character element of 
the Wide_String designated by Item. The result is the null Wide_String 
if the value of the formal parameter is the null Wide_String. The lower 
bound of the result Wide_String is 1.
Implementation Advice
 The string returned by Character_Set_Version should 
include either “10646:” or “Unicode”.
8  The results returned by these functions 
may depend on which particular version of the 10646 standard is supported 
by the implementation (see 
2.1).
 
9  The case insensitive equality comparison 
routines provided in 
A.4.10, “
String 
Comparison” are also available for wide strings (see 
A.4.7). 
 
Ada 2005 and 2012 Editions sponsored in part by Ada-Europe