NAME¶

std::collate_byname - std::collate_byname

Synopsis¶

Defined in header <locale>
template< class CharT >
class collate_byname : public std::collate<CharT>;

std::collate_byname is a std::collate facet which encapsulates locale-specific
collation (comparison) and hashing of strings. Just like std::collate, it can be
imbued in std::regex and applied, by means of std::locale::operator(), directly to
all standard algorithms that expect a string comparison predicate.

Specializations¶

The standard library is guaranteed to provide the following specializations:

Defined in header <locale>
std::collate_byname<char> locale-specific collation of multibyte strings
std::collate_byname<wchar_t> locale-specific collation of wide strings

Member functions¶

constructor constructs a new collate_byname facet
(public member function)
destructor destroys a collate_byname facet
(protected member function)

std::collate_byname::collate_byname

explicit collate_byname( const char* name, std::size_t refs = 0 );
explicit collate_byname( const std::string& name, std::size_t refs = (since C++11)
0 );

Constructs a new std::collate_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::collate_byname::~collate_byname

protected:
~collate_byname();

Destroys the facet.

Inherited from std::collate

Member types¶

Member type Definition
char_type CharT
string_type std::basic_string<CharT>

Member functions¶

compare invokes do_compare
(public member function of std::collate<CharT>)
transform invokes do_transform
(public member function of std::collate<CharT>)
hash invokes do_hash
(public member function of std::collate<CharT>)

Protected member functions¶

do_compare compares two strings using this facet's collation rules
[virtual] (virtual protected member function of std::collate<CharT>)
do_transform transforms a string so that collation can be replaced by comparison
[virtual] (virtual protected member function of std::collate<CharT>)
do_hash generates an integer hash value using this facet's collation rules
[virtual] (virtual protected member function of std::collate<CharT>)

Notes¶

Collation order is the dictionary order: the position of the letter in the national
alphabet (its equivalence class) has higher priority than its case or variant.
Within an equivalence class, lowercase characters collate before their uppercase
equivalents and locale-specific order may apply to the characters with diacritics.
In some locales, groups of characters compare as single collation units. For
example, "ch" in Czech follows "h" and precedes "i", and "dzs" in Hungarian follows
"dz" and precedes "g".

Example¶

This section is incomplete
Reason: no example

See also¶

collate defines lexicographical comparison and hashing of strings
(class template)
strcoll compares two strings in accordance to the current locale
(function)
wcscoll compares two wide strings in accordance to the current locale
(function)
operator() lexicographically compares two strings using this locale's collate facet
(public member function of std::locale)

Category:¶

* Todo no example