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diff --git a/src/boost/libs/program_options/example/regex.cpp b/src/boost/libs/program_options/example/regex.cpp
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+// Copyright Vladimir Prus 2002-2004.
+// Distributed under the Boost Software License, Version 1.0.
+// (See accompanying file LICENSE_1_0.txt
+// or copy at http://www.boost.org/LICENSE_1_0.txt)
+
+// This example shows how a user-defined class can be parsed using
+// specific mechanism -- not the iostream operations used by default.
+//
+// A new class 'magic_number' is defined and the 'validate' method is overloaded
+// to validate the values of that class using Boost.Regex.
+// To test, run
+//   
+//    regex -m 123-456
+//    regex -m 123-4567
+// 
+// The first invocation should output:
+//
+//   The magic is "456"
+//
+// and the second invocation should issue an error message.
+
+#include <boost/program_options.hpp>
+#include <boost/regex.hpp>
+
+using namespace boost;
+using namespace boost::program_options;
+
+#include <iostream>
+using namespace std;
+
+/* Define a completely non-sensical class. */
+struct magic_number {
+public:
+    magic_number(int n) : n(n) {}
+    int n;
+};
+
+/* Overload the 'validate' function for the user-defined class.
+   It makes sure that value is of form XXX-XXX 
+   where X are digits and converts the second group to an integer.
+   This has no practical meaning, meant only to show how
+   regex can be used to validate values.
+*/
+void validate(boost::any& v, 
+              const std::vector<std::string>& values,
+              magic_number*, int)
+{
+    static regex r("\\d\\d\\d-(\\d\\d\\d)");
+
+    using namespace boost::program_options;
+
+    // Make sure no previous assignment to 'a' was made.
+    validators::check_first_occurrence(v);
+    // Extract the first string from 'values'. If there is more than
+    // one string, it's an error, and exception will be thrown.
+    const string& s = validators::get_single_string(values);
+
+    // Do regex match and convert the interesting part to 
+    // int.
+    smatch match;
+    if (regex_match(s, match, r)) {
+        v = any(magic_number(lexical_cast<int>(match[1])));
+    } else {
+        throw validation_error(validation_error::invalid_option_value);
+    }        
+}
+
+
+int main(int ac, char* av[])
+{
+    try {
+        options_description desc("Allowed options");
+        desc.add_options()
+            ("help", "produce a help screen")
+            ("version,v", "print the version number")
+            ("magic,m", value<magic_number>(), 
+                 "magic value (in NNN-NNN format)")
+            ;
+        
+        variables_map vm;
+        store(parse_command_line(ac, av, desc), vm);
+   
+        if (vm.count("help")) {
+            cout << "Usage: regex [options]\n";
+            cout << desc;
+            return 0;
+        }
+        if (vm.count("version")) {
+            cout << "Version 1.\n";
+            return 0;
+        }
+        if (vm.count("magic")) {
+            cout << "The magic is \"" 
+                 << vm["magic"].as<magic_number>().n << "\"\n";
+        }
+    }
+    catch(std::exception& e)
+    {
+        cout << e.what() << "\n";
+    }    
+}