STD::__CXX11_COLLATE(3)

✨ NAME ✨

std::__cxx11::collate< _CharT > — bestie, this is the facet for localized string comparison. It's the little gremlin that knows how your language wants strings sorted. 💅

This page lives in the Library Functions Manual, so like… C++ standard library territory, okurrr. 🦋

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🎀 SYNOPSIS 🎀

#include <locale>

Inherits std::locale::facet. Yes queen, it's a facet, it's giving locale royalty. 👑

🌸 Public Types

• typedef _CharT char_type — public typedefs, cute and simple.
• typedef basic_string< _CharT > string_type — public typedefs, the stringy one.

🌈 Public Member Functions

• collate (__c_locale __cloc, size_t __refs=0) — internal constructor. Not for general use, so don't come for it unless you're the library itself.
• collate (size_t __refs=0) — constructor performs initialization.
• int _M_compare (const _CharT *, const _CharT *) const throw () — lowkey internal, no description given, we move.
• size_t _M_transform (_CharT *, const _CharT *, size_t) const throw () — also internal, also just vibing there.
• int compare (const _CharT *__lo1, const _CharT *__hi1, const _CharT *__lo2, const _CharT *__hi2) const — compare two strings.
• long hash (const _CharT *__lo, const _CharT *__hi) const — return hash of a string.
• string_type transform (const _CharT *__lo, const _CharT *__hi) const — transform string to comparable form.

⭐ Static Public Attributes

• static locale::id id — numpunct facet id.

🧚 Protected Member Functions

• virtual ~collate () — destructor.
• virtual int do_compare (const _CharT *__lo1, const _CharT *__hi1, const _CharT *__lo2, const _CharT *__hi2) const — compare two strings.
• virtual long do_hash (const _CharT *__lo, const _CharT *__hi) const — return hash of a string.
• virtual string_type do_transform (const _CharT *__lo, const _CharT *__hi) const — transform string to comparable form.

🫶 Static Protected Member Functions

• static __c_locale _S_clone_c_locale (__c_locale &__cloc) throw ()
• static void _S_create_c_locale (__c_locale &__cloc, const char *__s, __c_locale __old=0)
• static void _S_destroy_c_locale (__c_locale &__cloc)
• static __c_locale _S_get_c_locale ()
• static const char * _S_get_c_name () throw ()
• static __c_locale _S_lc_ctype_c_locale (__c_locale __cloc, const char *__s)

💜 Protected Attributes

• __c_locale _M_c_locale_collate

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💖 Detailed Description 💖

template<typename _CharT>
class std::__cxx11::collate< _CharT >"Facet for localized string comparison.

This facet encapsulates the code to compare strings in a localized manner. Fr fr, that's its whole job. 🌍

The collate template uses protected virtual functions to provide the actual results. The public accessors forward the call to the virtual functions. These virtual functions are hooks for developers to implement the behavior they require from the collate facet. So the public ones are like the front desk and the do_ ones are the actual main characters doing the work. ✨

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🌟 Member Typedef Documentation 🌟

• template<typename _CharT> typedef _CharT std::__cxx11::collate< _CharT >::char_type — public typedefs.
• template<typename _CharT> typedef basic_string<_CharT> std::__cxx11::collate< _CharT >::string_type — public typedefs.

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🎂 Constructor & Destructor Documentation 🎂

collate (size_t __refs = 0)

template<typename _CharT> std::__cxx11::collate< _CharT >::collate (size_t __refs = 0) [inline], [explicit]

Constructor performs initialization. This is the constructor provided by the standard. 💖

Parameters

• __refs — passed to the base facet class.

References std::locale::facet::facet().

Referenced by do_compare(), do_hash(), and do_transform().

collate (__c_locale __cloc, size_t __refs = 0)

template<typename _CharT> std::__cxx11::collate< _CharT >::collate (__c_locale __cloc, size_t __refs = 0) [inline], [explicit]

Internal constructor. Not for general use. This is a constructor for use by the library itself to set up new locales. Like, backstage access only, bestie, no VIPs allowed. 🙈

Parameters

• __cloc — the C locale.
• __refs — passed to the base facet class.

References std::locale::facet::facet().

~collate ()

template<typename _CharT> virtual std::__cxx11::collate< _CharT >::~collate () [inline], [protected], [virtual]

Destructor. She's protected, she's virtual, she's leaving the group chat. 💀

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🔥 Member Function Documentation 🔥

compare

template<typename _CharT> int std::__cxx11::collate< _CharT >::compare (const _CharT * __lo1, const _CharT * __hi1, const _CharT * __lo2, const _CharT * __hi2) const [inline]

Compare two strings. This function compares two strings and returns the result by calling collate::do_compare().

Parameters

• __lo1 — start of string 1.
• __hi1 — end of string 1.
• __lo2 — start of string 2.
• __hi2 — end of string 2.

Returns

1 if string1 > string2, -1 if string1 < string2, else 0.

References do_compare().

do_compare

template<typename _CharT> int std::collate< _CharT >::do_compare (const _CharT * __lo1, const _CharT * __hi1, const _CharT * __lo2, const _CharT * __hi2) const [protected], [virtual]

Compare two strings. This function is a hook for derived classes to change the value returned.

See also

compare().

Parameters

• __lo1 — start of string 1.
• __hi1 — end of string 1.
• __lo2 — start of string 2.
• __hi2 — end of string 2.

Returns

1 if string1 > string2, -1 if string1 < string2, else 0.

References collate(), std::basic_string< _CharT, _Traits, _Alloc >::c_str(), std::basic_string< _CharT, _Traits, _Alloc >::data(), and std::basic_string< _CharT, _Traits, _Alloc >::length().

Referenced by compare().

do_hash

template<typename _CharT> long std::collate< _CharT >::do_hash (const _CharT * __lo, const _CharT * __hi) const [protected], [virtual]

Return hash of a string. This function computes and returns a hash on the input string. This function is a hook for derived classes to change the value returned.

Parameters

• __lo — start of string.
• __hi — end of string.

Returns

Hash value.

References collate().

Referenced by hash().

do_transform

template<typename _CharT> collate< _CharT >::string_type std::collate< _CharT >::do_transform (const _CharT * __lo, const _CharT * __hi) const [protected], [virtual]

Transform string to comparable form. This function is a hook for derived classes to change the value returned.

Parameters

• __lo — start.
• __hi — end.

Returns

transformed string.

References collate(), std::basic_string< _CharT, _Traits, _Alloc >::append(), std::basic_string< _CharT, _Traits, _Alloc >::c_str(), std::basic_string< _CharT, _Traits, _Alloc >::clear(), std::basic_string< _CharT, _Traits, _Alloc >::data(), std::basic_string< _CharT, _Traits, _Alloc >::length(), and std::basic_string< _CharT, _Traits, _Alloc >::push_back().

Referenced by transform().

hash

template<typename _CharT> long std::__cxx11::collate< _CharT >::hash (const _CharT * __lo, const _CharT * __hi) const [inline]

Return hash of a string. This function computes and returns a hash on the input string. It does so by returning collate::do_hash().

Parameters

• __lo — start of string.
• __hi — end of string.

Returns

Hash value.

References do_hash().

transform

template<typename _CharT> string_type std::__cxx11::collate< _CharT >::transform (const _CharT * __lo, const _CharT * __hi) const [inline]

Transform string to comparable form. This function is a wrapper for strxfrm functionality. It takes the input string and returns a modified string that can be directly compared to other transformed strings. In the C locale, this function just returns a copy of the input string. In some other locales, it may replace two chars with one, change a char for another, etc. It does so by returning collate::do_transform().

Parameters

• __lo — start of string.
• __hi — end of string.

Returns

Transformed string_type.

References do_transform().

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👑 Member Data Documentation 👑

template<typename _CharT> locale::id std::__cxx11::collate< _CharT >::id [static]

Numpunct facet id.

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🍓 Author 🍓

Generated automatically by Doxygen for libstdc++ from the source code.

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Okay so that's the whole thing, bestie — every flag, every hook, every do_ function accounted for, no cap. 🫶

Signing off from the libstdc++ era, auto-generated by Doxygen straight from the source code. Go forth and sort your strings locally. Periodt. 💅✨