std::ctype_byname

 

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Symbols index

External libraries

 

Localization library

Locales and facets
Locales
has_facet use_facet	locale
Facet category base classes
ctype_base codecvt_base messages_base	time_base money_base
ctype facets
ctype ctype<char> ctype_byname	codecvt codecvt_byname
numeric facets
num_get num_put	numpunct numpunct_byname
collate facets
collate	collate_byname
time facets
time_get time_put	time_get_byname time_put_byname
monetary facets
money_get money_put	moneypunct moneypunct_byname
messages facets
messages	messages_byname

Character classification and conversion
Character classification
isspace isblank (C++11) iscntrl	isupper islower isalpha	ispunct isdigit isxdigit	isalnum isprint isgraph

Character conversions

toupper

tolower

String and stream conversions

wstring_convert (C++11/17/26*)

wbuffer_convert (C++11/17/26*)

Text encoding identifications

text_encoding (C++26)

Unicode conversion facets

codecvt_utf8 (C++11/17/26*)

codecvt_utf16 (C++11/17/26*)

codecvt_utf8_utf16 (C++11/17/26*)

codecvt_mode (C++11/17/26*)

C library locales
LC_ALLLC_COLLATELC_CTYPELC_MONETARYLC_NUMERICLC_TIME	setlocale localeconv lconv

 

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Defined in header <locale>

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template< class CharT >
class ctype_byname : public std::ctype<CharT>;

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std::ctype_byname is a std::ctype facet which encapsulates character classification rules of the locale specified at its construction.

Two specializations are provided by the standard library

Defined in header <locale>
std::ctype_byname<char>	provides narrow character classification. This specialization uses table lookup for character classification
std::ctype_byname<wchar_t>	provides wide character classification

Member types

Member type	Definition
mask	ctype<charT>::mask

Member functions

(constructor)	constructs a new ctype_byname facet (public member function)
(destructor)	destructs a ctype_byname facet (protected member function)

Inherited from std::ctype<CharT>

Member types

Member type	Definition
char_type	CharT

Member objects

Member name	Type
static std::locale::id id [static]	id of the locale (public static member constant)
if CharT is char, the following member of std::ctype<char> is inherited
static const std::size_t table_size [static]	size of the classification table, at least 256 (public static member constant)

Member functions

is	invokes do_is (public member function of std::ctype<CharT>)
scan_is	invokes do_scan_is (public member function of std::ctype<CharT>)
scan_not	invokes do_scan_not (public member function of std::ctype<CharT>)
toupper	invokes do_toupper (public member function of std::ctype<CharT>)
tolower	invokes do_tolower (public member function of std::ctype<CharT>)
widen	invokes do_widen (public member function of std::ctype<CharT>)
narrow	invokes do_narrow (public member function of std::ctype<CharT>)
if CharT is char, the following members of std::ctype<char> are inherited
table	obtains the character classification table (public member function of std::ctype<char>)
classic_table [static]	obtains the "C" locale character classification table (public static member function of std::ctype<char>)

Protected member functions

do_toupper [virtual]	converts a character or characters to uppercase (virtual protected member function of std::ctype<CharT>)
do_tolower [virtual]	converts a character or characters to lowercase (virtual protected member function of std::ctype<CharT>)
do_widen [virtual]	converts a character or characters from char to CharT (virtual protected member function of std::ctype<CharT>)
do_narrow [virtual]	converts a character or characters from CharT to char (virtual protected member function of std::ctype<CharT>)
if CharT is char, the following members of std::ctype are NOT inherited
do_is [virtual]	classifies a character or a character sequence (virtual protected member function of std::ctype<CharT>)
do_scan_is [virtual]	locates the first character in a sequence that conforms to given classification (virtual protected member function of std::ctype<CharT>)
do_scan_not [virtual]	locates the first character in a sequence that fails given classification (virtual protected member function of std::ctype<CharT>)

Inherited from std::ctype_base

Member types

Type	Definition
mask	unspecified bitmask type (enumeration, integer type, or bitset)

Member constants

space [static]	the value of mask identifying whitespace character classification (public static member constant)
print [static]	the value of mask identifying printable character classification (public static member constant)
cntrl [static]	the value of mask identifying control character classification (public static member constant)
upper [static]	the value of mask identifying uppercase character classification (public static member constant)
lower [static]	the value of mask identifying lowercase character classification (public static member constant)
alpha [static]	the value of mask identifying alphabetic character classification (public static member constant)
digit [static]	the value of mask identifying digit character classification (public static member constant)
punct [static]	the value of mask identifying punctuation character classification (public static member constant)
xdigit [static]	the value of mask identifying hexadecimal digit character classification (public static member constant)
blank [static] (C++11)	the value of mask identifying blank character classification (public static member constant)
alnum [static]	alpha | digit (public static member constant)
graph [static]	alnum | punct (public static member constant)

See also

Template:cpp/locale/dcl list ctypeTemplate:cpp/locale/dcl list ctype char