table of contents
std::match_results::size(3) | C++ Standard Libary | std::match_results::size(3) |
NAME¶
std::match_results::size - std::match_results::size
Synopsis¶
size_type size() const noexcept; (since C++11)
Returns the number of submatches, i.e. std::distance(begin(), end()).
Returns 0 if *this does not represent the result of a successful match.
Parameters¶
(none)
Return value¶
The number of submatches
Complexity¶
Constant
Example¶
// Run this code
#include <iostream>
#include <regex>
#include <string>
int main()
{
std::regex re("a(a)*b");
std::string target("aaab");
std::smatch sm;
std::cout << sm.size() << '\n';
std::regex_match(target, sm, re);
std::cout << sm.size() << '\n';
}
Output:¶
0
2
See also¶
begin returns iterator to the beginning of the list of
sub-matches
cbegin (public member function)
end returns iterator to the end of the list of sub-matches
cend (public member function)
2022.07.31 | http://cppreference.com |