std::isalpha(std::locale)

 

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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    iscntrl isupper islower    isalpha ispunct isdigit    isxdigit isalnum isblank (C++11) isprint isgraph Character conversions toupper    tolower String and stream conversions wstring_convert (C++11/17/26*) wbuffer_convert (C++11/17/26*) 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

 

Defined in header <locale>
template<class CharT > bool isalpha( CharT ch, const locale& loc );

Checks if the given character is classified as an alphabetic character by the given locale's std::ctype facet.

Parameters

ch	-	character
loc	-	locale

Return value

Returns true if the character is classified as alphabetic, false otherwise.

Possible implementation

template<class CharT>bool isalpha(CharT ch, conststd::locale& loc){returnstd::use_facet<std::ctype<CharT>>(loc).is(std::ctype_base::alpha, ch);}

Example

Demonstrates the use of isalpha() with different locales (OS-specific).

Run this code

#include <iostream>#include <locale>   int main(){constwchar_t c = L'\u042f';// cyrillic capital letter ya   std::locale loc1("C");std::cout<<"isalpha('Я', C locale) returned "<<std::boolalpha<<std::isalpha(c, loc1)<<'\n';   std::locale loc2("en_US.UTF8");std::cout<<"isalpha('Я', Unicode locale) returned "<<std::boolalpha<<std::isalpha(c, loc2)<<'\n';}

Possible output:

isalpha('Я', C locale) returned false isalpha('Я', Unicode locale) returned true

See also

isalpha	checks if a character is alphabetic (function)
iswalpha	checks if a wide character is alphabetic (function)