std::ctype<CharT>::scan_not, std::ctype<CharT>::do_scan_not

 

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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

 

std::ctype

Member functions

ctype::ctype

ctype::~ctype

ctype::isctype::do_is

ctype::scan_isctype::do_scan_is

ctype::scan_notctype::do_scan_not

ctype::toupperctype::do_toupper

ctype::tolowerctype::do_tolower

ctype::widenctype::do_widen

ctype::narrowctype::do_narrow

Member functions of ctype<char>

ctype<char>::ctype

ctype<char>::~ctype

ctype<char>::table

ctype<char>::classic_table

ctype<char>::is

ctype<char>::scan_is

ctype<char>::scan_not

 

Defined in header <locale>
public: const CharT* scan_not( mask m, const CharT* beg, const CharT* end ) const;	(1)
protected: virtual const CharT* do_scan_not( mask m, const CharT* beg, const CharT* end ) const;	(2)

1) Public member function, calls the protected virtual member function do_scan_not of the most derived class.

2) Locates the first character in the character array [beg, end) that does not satisfy the classification mask m, that is, the first character c such that is(m, c) would return false.

Parameters

m	-	mask to search for
beg	-	pointer to the first character in an array of characters to search
end	-	one past the end pointer for the array of characters to search

Return value

Pointer to the first character in [beg, end) that doesn't satisfy the mask, or end if no such character was found.

Example

Run this code

#include <clocale>
#include <iostream>
#include <iterator>
#include <locale>
 
int main()
{
    std::setlocale(LC_ALL, "en_US.utf8");
    std::wcout.imbue(std::locale("en_US.utf8");
    auto& f = std::use_facet<std::ctype<wchar_t>>(std::wcout.getloc();
 
    / skip leading whitespace
    wchar_t s1[] = L"      \t\t\n  Кошка";
    const wchar_t* p1 = f.scan_not(std::ctype_base::space, std::begin(s1), std::end(s1));
    std::wcout << '\'' << p1 << "'\n";
 
    / skip leading digits
    wchar_t s2[] = L"123456789ネプネプ";
    const wchar_t* p2 = f.scan_not(std::ctype_base::digit, std::begin(s2), std::end(s2));
    std::wcout << '\'' << p2 << "'\n";
}

Output:

'Кошка'
'ネプネプ'

See also

scan_not	locates the first character in a sequence that fails given classification, using the classification table (public member function of std::ctype<char>)
do_scan_is [virtual]	locates the first character in a sequence that conforms to given classification (virtual protected member function)

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