abort() called using std::regex to validate URL - c++

Question

#include <iostream>
#include <string>
#include <regex>
using namespace std;
int main ()
{
if (std::regex_match ("http://www.google.com", std::regex("(http|https):\/\/(\w+\.)*(\w*)\/([\w\d]+\/{0,1})+")))
std::cout << "valid URL \n";
std::cout << std::endl;
return 0;
}
its compiling with the warnings ,but when I executed it gives
terminate called after throwing an instance of 'std::regex_error'
what(): regex_error
Aborted (core dumped)
what I should Do?

Answer 1

The warnings that you are ignoring are probably telling you what the problem is.
By looking at the pattern, you have not properly escaped the pattern string.
Properly escaping the pattern string to use '\' to escape the backslash will solve the problem. Otherwise, the compiler is tring to interpret the character that follows the un-escaped backslash into a string control character.
std::regex("(http|https)://(\\w+.)(\\w)/([\\w\\d]+/{0,1})+")

Answer 2

Try cpp-netlib:
#include <string>
#include <iostream>
#include <boost/network/uri.hpp>
int main (int argc, char ** argv)
{
std::string address = "http://www.google.com";
boost::network::uri::uri uri_(address);
if ( !boost::network::uri::valid(uri_) )
{
// error
std::cout << "not valid" << std::endl;
return 0;
}
std::cout << "valid" << std::endl;
std::string host = boost::network::uri::host(uri_);
std::string port = boost::network::uri::port(uri_);
std::string scheme = boost::network::uri::scheme(uri_);
return 0;
}
How to build (cpp-netlib is in /root/cpp-netlib-0.9.4/ in my case):
g++ main.cpp -L/root/cpp-netlib-0.9.4/libs/network/src/ -I/root/cpp-netlib-0.9.4/ -o main -lcppnetlib-uri -lboost_system