Regex Extract Code

A regular expression can extract a structured part of a text record when the format is predictable.

regex_extract_code.cpp

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

int main() {
    std::string ticket = ;

    std::regex pattern("([A-Z]+)-([0-9]+)");
    std::smatch match;
    bool ok = std::regex_match(ticket, match, pattern);
    std::string prefix = ok ? match[1].str() : "none";
    std::string number = ok ? match[2].str() : "0";

    std::cout << "ok=" << ok << std::endl;
    std::cout << "prefix=" << prefix << std::endl;
    std::cout << "number=" << number << std::endl;
    return 0;
}

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

int main() {
    std::string ticket = ;

    std::regex pattern("([A-Z]+)-([0-9]+)");
    std::smatch match;
    bool ok = std::regex_match(ticket, match, pattern);
    std::string prefix = ok ? match[1].str() : "none";
    std::string number = ok ? match[2].str() : "0";

    std::cout << "ok=" << ok << std::endl;
    std::cout << "prefix=" << prefix << std::endl;
    std::cout << "number=" << number << std::endl;
    return 0;
}

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

int main() {
    std::string ticket = ;

    std::regex pattern("([A-Z]+)-([0-9]+)");
    std::smatch match;
    bool ok = std::regex_match(ticket, match, pattern);
    std::string prefix = ok ? match[1].str() : "none";
    std::string number = ok ? match[2].str() : "0";

    std::cout << "ok=" << ok << std::endl;
    std::cout << "prefix=" << prefix << std::endl;
    std::cout << "number=" << number << std::endl;
    return 0;
}

regex `std::regex` describes a text pattern.

match group Parentheses in a regex capture part of a match so the program can use it separately.