#include <regex>
#include <cassert>
int main()
{
{
std::regex phone_numbers("\\d{3}-\\d{4}");
const char phone_book[] = "555-1234, 555-2345, 555-3456";
std::string r = std::regex_replace(phone_book, phone_numbers,
std::string("123-$&"));
assert(r == "123-555-1234, 123-555-2345, 123-555-3456");
}
{
std::regex phone_numbers("\\d{3}-\\d{4}");
const char phone_book[] = "555-1234, 555-2345, 555-3456";
std::string r = std::regex_replace(phone_book, phone_numbers,
std::string("123-$&"),
std::regex_constants::format_sed);
assert(r == "123-$555-1234, 123-$555-2345, 123-$555-3456");
}
{
std::regex phone_numbers("\\d{3}-\\d{4}");
const char phone_book[] = "555-1234, 555-2345, 555-3456";
std::string r = std::regex_replace(phone_book, phone_numbers,
std::string("123-&"),
std::regex_constants::format_sed);
assert(r == "123-555-1234, 123-555-2345, 123-555-3456");
}
{
std::regex phone_numbers("\\d{3}-\\d{4}");
const char phone_book[] = "555-1234, 555-2345, 555-3456";
std::string r = std::regex_replace(phone_book, phone_numbers,
std::string("123-$&"),
std::regex_constants::format_no_copy);
assert(r == "123-555-1234123-555-2345123-555-3456");
}
{
std::regex phone_numbers("\\d{3}-\\d{4}");
const char phone_book[] = "555-1234, 555-2345, 555-3456";
std::string r = std::regex_replace(phone_book, phone_numbers,
std::string("123-$&"),
std::regex_constants::format_first_only);
assert(r == "123-555-1234, 555-2345, 555-3456");
}
{
std::regex phone_numbers("\\d{3}-\\d{4}");
const char phone_book[] = "555-1234, 555-2345, 555-3456";
std::string r = std::regex_replace(phone_book, phone_numbers,
std::string("123-$&"),
std::regex_constants::format_first_only |
std::regex_constants::format_no_copy);
assert(r == "123-555-1234");
}
}