Ada Reference Manual (Ada 2022) — Legal Information

# A.3.5 The Package Wide_Characters.Handling

1/3
The package Wide_Characters.Handling provides operations for classifying Wide_Characters and case folding for Wide_Characters.

#### Static Semantics

2/3
The library package Wide_Characters.Handling has the following declaration:
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package Ada.Wide_Characters.Handling
with Pure is
4/3
function Character_Set_Version return String;
5/3
function Is_Control (Item : Wide_Character) return Boolean;
6/3
function Is_Letter (Item : Wide_Character) return Boolean;
7/3
function Is_Lower (Item : Wide_Character) return Boolean;
8/3
function Is_Upper (Item : Wide_Character) return Boolean;
8.1/5
function Is_Basic (Item : Wide_Character) return Boolean;
9/3
function Is_Digit (Item : Wide_Character) return Boolean;
10/3
function Is_Decimal_Digit (Item : Wide_Character) return Boolean
renames Is_Digit;
11/3
function Is_Hexadecimal_Digit (Item : Wide_Character) return Boolean;
12/3
function Is_Alphanumeric (Item : Wide_Character) return Boolean;
13/3
function Is_Special (Item : Wide_Character) return Boolean;
14/3
function Is_Line_Terminator (Item : Wide_Character) return Boolean;
15/3
function Is_Mark (Item : Wide_Character) return Boolean;
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function Is_Other_Format (Item : Wide_Character) return Boolean;
17/3
function Is_Punctuation_Connector (Item : Wide_Character) return Boolean;
18/3
function Is_Space (Item : Wide_Character) return Boolean;
18.1/5
function Is_NFKC (Item : Wide_Character) return Boolean;
19/3
function Is_Graphic (Item : Wide_Character) return Boolean;
20/3
function To_Lower (Item : Wide_Character) return Wide_Character;
function To_Upper (Item : Wide_Character) return Wide_Character;
20.1/5
function To_Basic (Item : Wide_Character) return Wide_Character;
21/3
function To_Lower (Item : Wide_String) return Wide_String;
function To_Upper (Item : Wide_String) return Wide_String;
21.1/5
function To_Basic (Item : Wide_String) return Wide_String;
22/3
end Ada.Wide_Characters.Handling;
23/3
The subprograms defined in Wide_Characters.Handling are locale independent.
24/3
function Character_Set_Version return String;
25/3
Returns an implementation-defined identifier that identifies the version of the character set standard that is used for categorizing characters by the implementation.
26/3
function Is_Control (Item : Wide_Character) return Boolean;
27/3
Returns True if the Wide_Character designated by Item is categorized as other_control; otherwise returns False.
28/3
function Is_Letter (Item : Wide_Character) return Boolean;
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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.
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function Is_Lower (Item : Wide_Character) return Boolean;
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Returns True if the Wide_Character designated by Item is categorized as letter_lowercase; otherwise returns False.
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function Is_Upper (Item : Wide_Character) return Boolean;
33/3
Returns True if the Wide_Character designated by Item is categorized as letter_uppercase; otherwise returns False.
33.1/5
function Is_Basic (Item : Wide_Character) return Boolean;
33.2/5
Returns True if the Wide_Character designated by Item has no Decomposition Mapping in the code charts of ISO/IEC 10646:2020; otherwise returns False.
34/3
function Is_Digit (Item : Wide_Character) return Boolean;
35/3
Returns True if the Wide_Character designated by Item is categorized as number_decimal; otherwise returns False.
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function Is_Hexadecimal_Digit (Item : Wide_Character) return Boolean;
37/3
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.
38/3
function Is_Alphanumeric (Item : Wide_Character) return Boolean;
39/3
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.
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function Is_Special (Item : Wide_Character) return Boolean;
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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.
42/3
function Is_Line_Terminator (Item : Wide_Character) return Boolean;
43/3
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.
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function Is_Mark (Item : Wide_Character) return Boolean;
45/3
Returns True if the Wide_Character designated by Item is categorized as mark_non_spacing or mark_spacing_combining; otherwise returns False.
46/3
function Is_Other_Format (Item : Wide_Character) return Boolean;
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Returns True if the Wide_Character designated by Item is categorized as other_format; otherwise returns False.
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function Is_Punctuation_Connector (Item : Wide_Character) return Boolean;
49/3
Returns True if the Wide_Character designated by Item is categorized as punctuation_connector; otherwise returns False.
50/3
function Is_Space (Item : Wide_Character) return Boolean;
51/3
Returns True if the Wide_Character designated by Item is categorized as separator_space; otherwise returns False.
51.1/5
function Is_NFKC (Item : Wide_Character) return Boolean;
51.2/5
Returns True if the Wide_Character designated by Item can be present in a string normalized to Normalization Form KC (as defined by Clause 22 of ISO/IEC 10646:2020), otherwise returns False.
52/3
function Is_Graphic (Item : Wide_Character) return Boolean;
53/3
Returns True if the Wide_Character designated by Item is categorized as graphic_character; otherwise returns False.
54/3
function To_Lower (Item : Wide_Character) return Wide_Character;
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Returns the Simple Lowercase Mapping as defined by documents referenced in Clause 2 of ISO/IEC 10646:2020 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.
56/3
function To_Lower (Item : Wide_String) return Wide_String;
57/3
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.
58/3
function To_Upper (Item : Wide_Character) return Wide_Character;
59/5
Returns the Simple Uppercase Mapping as defined by documents referenced in Clause 2 of ISO/IEC 10646:2020 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.
60/3
function To_Upper (Item : Wide_String) return Wide_String;
61/3
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.
61.1/5
function To_Basic (Item : Wide_Character) return Wide_Character;
61.2/5
Returns the Wide_Character whose code point is given by the first value of its Decomposition Mapping in the code charts of ISO/IEC 10646:2020 if any; returns Item otherwise.
61.3/5
function To_Basic (Item : Wide_String) return Wide_String;
61.4/5
Returns the result of applying the To_Basic 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

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The string returned by Character_Set_Version should include either “10646:” or “Unicode”.
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NOTE 1 The results returned by these functions can depend on which particular version of ISO/IEC 10646 is supported by the implementation (see 2.1).
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NOTE 2 The case insensitive equality comparison routines provided in A.4.10 are also available for wide strings (see A.4.7).

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