operator<<(std::sub_match)

 

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std::sub_match

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operator==operator!=operator<<operator<=operator>operator>=operator<=> (until C++20)(until C++20)(until C++20)(until C++20)(until C++20)(C++20)

operator<<

 

template< class CharT, class Traits, class BidirIt > std::basic_ostream<CharT,Traits>&     operator<<( std::basic_ostream<CharT,Traits>& os, const sub_match<BidirIt>& m );		(since C++11)

Writes the representation of the matched subsequence m to the output stream os. Equivalent to os << m.str().

Parameters

os	-	output stream to write the representation to
m	-	a sub-match object to output

Return value

os

Example

Run this code

#include <iostream>
#include <regex>
#include <string>
 
int main()
{
    std::string sentence{"Quick red fox jumped over a lazy hare."};
    const std::regex re{"([A-z]+) ([a-z]+) ([a-z]+)"};
    std::smatch words;
    std::regex_search(sentence, words, re);
    for (const auto& m : words)
        // m has type `const std::sub_match<std::string::const_iterator>&`
        std::cout << '[' << m << "] ";
    std::cout << '\n';
}

Output:

[Quick red fox] [Quick] [red] [fox]