The following code example is taken from the book
The C++ Standard Library - A Tutorial and Reference, 2nd Edition
by Nicolai M. Josuttis, Addison Wesley Longman, 2012
Copyright © 2012 by Pearson Education, Inc. and Nicolai M. Josuttis
#include <string>
#include <regex>
#include <iostream>
#include <iomanip>
using namespace std;
int main()
{
string data = "XML tag: <tag-name>the value</tag-name>.";
cout << "data: " << data << "\n\n";
smatch m; // for returned details of the match
bool found = regex_search (data,
m,
regex("<(.*)>(.*)</(\\1)>"));
// print match details:
cout << "m.empty(): " << boolalpha << m.empty() << endl;
cout << "m.size(): " << m.size() << endl;
if (found) {
cout << "m.str(): " << m.str() << endl;
cout << "m.length(): " << m.length() << endl;
cout << "m.position(): " << m.position() << endl;
cout << "m.prefix().str(): " << m.prefix().str() << endl;
cout << "m.suffix().str(): " << m.suffix().str() << endl;
cout << endl;
// iterating over all matches (using the match index):
for (int i=0; i<m.size(); ++i) {
cout << "m[" << i << "].str(): " << m[i].str() << endl;
cout << "m.str(" << i << "): " << m.str(i) << endl;
cout << "m.position(" << i << "): " << m.position(i)
<< endl;
}
cout << endl;
// iterating over all matches (using iterators):
cout << "matches:" << endl;
for (auto pos = m.begin(); pos != m.end(); ++pos) {
cout << " " << *pos << " ";
cout << "(length: " << pos->length() << ")" << endl;
}
}
}