std::ctype_byname
From cppreference.com
Defined in header <locale>
|
||
template< class CharT > class ctype_byname : public std::ctype<CharT>; |
||
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) |
destroys a ctype_byname facet (protected member function) |
std::ctype_byname::ctype_byname
explicit ctype_byname( const char* name, std::size_t refs = 0 ); |
||
explicit ctype_byname( const std::string& name, std::size_t refs = 0 ); |
(since C++11) | |
Constructs a new std::ctype_byname
facet for a locale with name
.
refs
is used for resource management: if refs == 0, the implementation destroys the facet, when the last std::locale object holding it is destroyed. Otherwise, the object is not destroyed.
Parameters
name | - | the name of the locale |
refs | - | the number of references that link to the facet |
std::ctype_byname::~ctype_byname
protected: ~ctype_byname(); |
||
Destroys the facet.
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
invokes do_is (public member function of std::ctype<CharT> ) | |
invokes do_scan_is (public member function of std::ctype<CharT> ) | |
invokes do_scan_not (public member function of std::ctype<CharT> ) | |
invokes do_toupper (public member function of std::ctype<CharT> ) | |
invokes do_tolower (public member function of std::ctype<CharT> ) | |
invokes do_widen (public member function of std::ctype<CharT> ) | |
invokes do_narrow (public member function of std::ctype<CharT> ) | |
if CharT is char, the following members of std::ctype<char> are inherited | |
obtains the character classification table (public member function of std::ctype<char> ) | |
[static] |
obtains the "C" locale character classification table (public static member function of std::ctype<char> ) |
Protected member functions
[virtual] |
converts a character or characters to uppercase (virtual protected member function of std::ctype<CharT> ) |
[virtual] |
converts a character or characters to lowercase (virtual protected member function of std::ctype<CharT> ) |
[virtual] |
converts a character or characters from char to charT (virtual protected member function of std::ctype<CharT> ) |
[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 | |
[virtual] |
classifies a character or a character sequence (virtual protected member function of std::ctype<CharT> ) |
[virtual] |
locates the first character in a sequence that conforms to given classification (virtual protected member function of std::ctype<CharT> ) |
[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) |
Notes
The explicit specialization std::ctype_byname<char> was listed as a separate entry in the header file <locale>
until C++11. it was removed in C++11 as defect #1298, but it remains a required specialization, just like std::ctype_byname<wchar_t>
.
Example
Run this code
#include <iostream> #include <locale> int main() { wchar_t c = L'\u00de'; // capital letter thorn std::locale loc("C"); std::cout << "isupper('Þ', C locale) returned " << std::boolalpha << std::isupper(c, loc) << '\n'; loc = std::locale(loc, new std::ctype_byname<wchar_t>("en_US.utf8")); std::cout << "isupper('Þ', C locale with Unicode ctype) returned " << std::boolalpha << std::isupper(c, loc) << '\n'; }
Output:
isupper('Þ', C locale) returned false isupper('Þ', C locale with Unicode ctype) returned true
See also
defines character classification tables (class template) | |
specialization of std::ctype for type char (class template specialization) |