std::tolower(std::locale)

 

C++

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Localizations library

Locales and facets
locale
use_facet	has_facet
Character classification
isspace isblank (C++11) iscntrl isupper islower isalpha	isdigit ispunct isxdigit isalnum isprint isgraph
Conversions
toupper tolower	wstring_convert (C++11) wbuffer_convert (C++11)
Facet category base classes
ctype_base codecvt_base messages_base	time_base money_base
Facet categories
ctype ctype<char> codecvt collate messages time_get time_put	num_get num_put numpunct money_get money_put moneypunct
Locale-specific facets
ctype_byname ctype_byname<char> codecvt_byname messages_byname collate_byname	time_get_byname time_put_byname numpunct_byname moneypunct_byname
Code conversion facets
codecvt_utf8 (C++11) codecvt_utf16 (C++11)	codecvt_utf8_utf16 (C++11) codecvt_mode (C++11)
C locale
setlocale localeconv lconv	LC_ALL LC_COLLATE LC_CTYPE LC_MONETARY LC_NUMERIC LC_TIME

 

Defined in header <locale>
template< class charT > charT tolower( charT ch, const locale& loc );

Converts the character ch to lowercase if possible, using the conversion rules specified by the given locale's std::ctype facet.

Parameters

ch	-	character
loc	-	locale

Return value

Returns the lowercase form of ch if one is listed in the locale, otherwise return ch unchanged.

Notes

Only 1:1 character mapping can be performed by this function, e.g. the Greek uppercase letter 'Σ' has two lowercase forms, depending on the position in a word: 'σ' and 'ς'. A call to std::tolower cannot be used to obtain the correct lowercase form in this case.

Possible implementation

template< class charT > charT tolower( charT ch, const std::locale& loc ) { return std::use_facet<std::ctype<charT>>(loc).tolower(ch); }

See also

toupper(std::locale)	converts a character to uppercase using the ctype facet of a locale (function template)
tolower	converts a character to lowercase (function)
towlower	converts a wide character to lowercase (function)