Add module support and tests. (#174)

test/module/partial_regex_match.cpp

@@ -0,0 +1,81 @@
+/*
+ *
+ * Copyright (c) 1998-2022
+ * John Maddock
+ *
+ * Use, modification and distribution are subject to 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)
+ *
+ */
+
+ /*
+  *   LOCATION:    see http://www.boost.org for most recent version.
+  *   FILE         partial_regex_match.cpp
+  *   VERSION      see <boost/version.hpp>
+  *   DESCRIPTION: regex_match example using partial matches.
+  */
+
+
+//#include <version>
+
+#if (defined(__cpp_lib_modules) || (defined(_MSC_FULL_VER) && (_MSC_FULL_VER >= 193833135))) && !defined(TEST_HEADERS)
+import std;
+#elif defined(MSVC_EXPERIMENTAL_STD_MODULE) && !defined(TEST_HEADERS)
+import std.core;
+#else
+#include <string>
+#include <iostream>
+#endif
+
+#ifdef TEST_HEADERS
+#include <boost/regex.hpp>
+#else
+import boost.regex;
+#endif
+
+boost::regex e("(\\d{3,4})[- ]?(\\d{4})[- ]?(\\d{4})[- ]?(\\d{4})");
+
+bool is_possible_card_number(const std::string& input)
+{
+   //
+   // return false for partial match, true for full match, or throw for
+   // impossible match based on what we have so far...
+   boost::match_results<std::string::const_iterator> what;
+   if(0 == boost::regex_match(input, what, e, boost::match_default | boost::match_partial))
+   {
+      // the input so far could not possibly be valid so reject it:
+      throw std::runtime_error("Invalid data entered - this could not possibly be a valid card number");
+   }
+   // OK so far so good, but have we finished?
+   if(what[0].matched)
+   {
+      // excellent, we have a result:
+      return true;
+   }
+   // what we have so far is only a partial match...
+   return false;
+}
+
+int main(int argc, char* argv[])
+{
+   try{
+      std::string input;
+      if(argc > 1)
+         input = argv[1];
+      else
+         std::cin >> input;
+      if(is_possible_card_number(input))
+      {
+         std::cout << "Matched OK..." << std::endl;
+      }
+      else
+         std::cout << "Got a partial match..." << std::endl;
+   }
+   catch(const std::exception& e)
+   {
+      std::cout << e.what() << std::endl;
+   }
+   return 0;
+}
+