Added to trunk

[SVN r70067]

example/doc_how_works.cpp

@@ -0,0 +1,60 @@
+//////////////////////////////////////////////////////////////////////////////
+//
+// (C) Copyright Ion Gaztanaga 2009.
+// 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)
+//
+// See http://www.boost.org/libs/move for documentation.
+//
+//////////////////////////////////////////////////////////////////////////////
+
+#include <boost/config.hpp>
+
+#if !defined(BOOST_NO_RVALUE_REFERENCES)
+
+int main()
+{
+   return 0;
+}
+
+#else
+
+//[how_works_example
+#include <boost/move/move.hpp>
+#include <iostream>
+
+class sink_tester
+{
+   public: //conversions provided by BOOST_COPYABLE_AND_MOVABLE
+   operator ::boost::rv<sink_tester>&()
+      {  return *static_cast< ::boost::rv<sink_tester>* >(this);  }
+   operator const ::boost::rv<sink_tester>&() const
+      {  return *static_cast<const ::boost::rv<sink_tester>* >(this);  }
+};
+
+//Functions returning different r/lvalue types
+      sink_tester    rvalue()       {  return sink_tester(); }
+const sink_tester    const_rvalue() {  return sink_tester(); }
+      sink_tester &  lvalue()       {  static sink_tester lv; return lv; }
+const sink_tester &  const_lvalue() {  static const sink_tester clv = sink_tester(); return clv; }
+
+//BOOST_RV_REF overload
+void sink(::boost::rv<sink_tester> &)      { std::cout << "non-const rvalue catched" << std::endl; }
+//BOOST_COPY_ASSIGN_REF overload
+void sink(const ::boost::rv<sink_tester> &){ std::cout << "const (r-l)value catched" << std::endl; }
+//Overload provided by BOOST_COPYABLE_AND_MOVABLE
+void sink(sink_tester &)                   { std::cout << "non-const lvalue catched" << std::endl; }
+
+int main()
+{
+   sink(const_rvalue());   //"const (r-l)value catched"
+   sink(const_lvalue());   //"const (r-l)value catched"
+   sink(lvalue());         //"non-const lvalue catched"
+   sink(rvalue());         //"non-const rvalue catched"
+   return 0;
+}
+//]
+
+#endif
+