std::wctype - cppreference.com

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std::wctype_twctype(constchar*str);Constructs a value of type std::wctype_t that describes a

LC_CTYPE

category of wide character classification. It may be one of the standard classification categories, or a locale-specific category, such as "jkanji".

Parameters

str - C string holding the name of the desired category The following values of str are supported in all C locales:

value of streffect "alnum"identifies the category used by

std::iswalnum

"alpha"identifies the category used by

std::iswalpha

"blank"identifies the category used by

std::iswblank

(C++11)"cntrl"identifies the category used by

std::iswcntrl

"digit"identifies the category used by

std::iswdigit

"graph"identifies the category used by

std::iswgraph

"lower"identifies the category used by

std::iswlower

"print"identifies the category used by

std::iswprint

"space"identifies the category used by

std::iswspace

"upper"identifies the category used by

std::iswupper

"xdigit"identifies the category used by

std::iswxdigit

Return value

std::wctype_t object suitable for use with

std::iswctype

to classify wide characters according to the named category of the current C locale or zero if str does not name a category supported by the current C locale.

See also