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std::match_results::ready(3) C++ Standard Libary std::match_results::ready(3)

NAME

std::match_results::ready - std::match_results::ready

Synopsis


bool ready() const; (since C++11)


Indicates if the match results are ready (valid) or not.


A default-constructed match result has no result state (is not ready), and can only
be made ready by one of the regex algorithms. The ready state implies that all match
results have been fully established.


The result of calling most member functions of the match_results object that is not
ready is undefined.

Return value


true if the match results are ready, false otherwise.

Example

// Run this code


#include <iostream>
#include <regex>
#include <string>


int main()
{
std::string target("pattern");
std::smatch sm;
std::cout << "default constructed smatch is "
<< (sm.ready() ? " ready\n" : " not ready\n");


std::regex re1("tte");
std::regex_search(target, sm, re1);


std::cout << "after search, smatch is "
<< (sm.ready() ? " ready\n" : " not ready\n");
}

Output:


default constructed smatch is not ready
after search, smatch is ready

2022.07.31 http://cppreference.com