How do I convert a regular expression match into a "struct"?

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Regular Expression: ([0-9]*)|([0-9]*\.[0-9]*)
String: word1 word2 0:12:13.23456 ... example string match: 0,12,13.23456

Requirement:
convert to a struct ->

struct Duration {
    unsigned int hours;
    unsigned int minutes;
    double seconds;
};

Current matcher:

Duration duration;
std::regex regex("([0-9]*):([0-9]*):([0-9]*.[0-9]*)");
auto begin = std::sregex_iterator(data.begin(), data.end(), regex); // data is an std::string instance
auto end = std::sregex_iterator();
for (auto it = begin; it != end; it++) {
    auto match = *it;
    // how to cycle through the data values of the instance of Duration?            
}
data-conversion struct c++ regex
1 Answers

I recommend using std::regex_search instead of iterators and loops. Then you get a match result which you can index to get the separate matches.

Once you have the separate matches, you can call std::stoul or std::stod to convert the matched strings to their numeric variants.

Perhaps something like this:

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

struct Duration
{
    unsigned int hours;
    unsigned int minutes;
    double seconds;
};

int main()
{
    std::string input = "word1 word2 0:12:13.23456";
    std::regex regex("([0-9]*):([0-9]*):([0-9]*.[0-9]*)");
    std::smatch matches;

    std::regex_search(input, matches, regex);

    Duration duration = {
        static_cast<unsigned int>(std::stoul(matches[1])),
        static_cast<unsigned int>(std::stoul(matches[2])),
        std::stod(matches[3])
    };

    std::cout << "Duration = { " << duration.hours << ", " << duration.minutes << ", " << duration.seconds << " }\n";
}

[Note: There's no error checking, or checking the amount of actual matches in matches, which should really be done in a "real" program]

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