std::regex_traits::length

static std::size_t length(const char_type* p);

Calculates the length of a null-terminated character sequence, that is, the smallest i such that p[i]==0.

Standard library specializations of std::regex_traits execute std::char_traits<CharT>::length(p);

Parameters

Return value

The length of the null-terminated character string.

Example

#include <regex>
#include <iostream>
 
int main()
{
    std::cout << std::regex_traits<char>::length(u8"Кошка") << '\n'
              << std::regex_traits<wchar_t>::length(L"Кошка") << '\n';
}

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