regexConsole.cpp

/*
 * A short example to demonstrate stream IO and regex pattern matching.
 */
 
#include <iostream>
#include <regex>
#include <z/core/string.hpp>
 
int main() {
    std::regex regex;
    zstring pattern;
 
    while (!std::cin.eof()) {
        // Get regex pattern to match against, exiting if user hits ctrl-D.
        pattern.readln(std::cin);
        if (std::cin.eof() && !pattern.length()) {
            break;
        }
 
        // If pattern is invalid, print a short description of the error.
        try {
            regex.assign(pattern.str());
        } catch (const std::regex_error &err) {
            zstring(err.what()).writeln(std::cout);
            continue;
        }
 
        // Prompt for the string to match to the regex pattern.
        // Note that zstring is equivalent to z::core::string<z::utf8>
        zstring(":").write(std::cout);
        zstring text;
        text.readln(std::cin);
 
        // Show what substring the regex matched, if anything.
        auto match = std::regex_search(text.str(), regex);
        if (std::regex_search(text.str(), regex)) {
            (text + " matches!").writeln(std::cout);
        } else {
            zstring("does not match.").writeln(std::cout);
        }
    }
 
    return 0;
}