add tuple example

[SVN r16633]

example/tuple_from_list.cpp

@@ -0,0 +1,50 @@
+//-----------------------------------------------------------------------------
+// boost mpl/example/tuple_from_list.cpp source file
+// See http://www.boost.org for updates, documentation, and revision history.
+//-----------------------------------------------------------------------------
+//
+// Copyright (c) 2002
+// Aleksey Gurtovoy
+//
+// Permission to use, copy, modify, distribute and sell this software
+// and its documentation for any purpose is hereby granted without fee, 
+// provided that the above copyright notice appears in all copies and 
+// that both the copyright notice and this permission notice appear in 
+// supporting documentation. No representations are made about the 
+// suitability of this software for any purpose. It is provided "as is" 
+// without express or implied warranty.
+
+#include "boost/mpl/fold_backward.hpp"
+#include "boost/mpl/list.hpp"
+#include "boost/mpl/assert_is_same.hpp"
+#include "boost/tuple/tuple.hpp"
+
+#include <iostream>
+
+using namespace boost::mpl;
+
+template< typename Types > struct tuple_gen
+    : fold_backward<
+          Types
+        , boost::tuples::null_type
+        , boost::tuples::cons<_2,_1>
+        >
+{
+};
+
+int main()
+{
+    tuple_gen< list<int,char const*,bool> >::type t;
+    
+    boost::get<0>(t) = -1;
+    boost::get<1>(t) = "text";
+    boost::get<2>(t) = false;
+
+    std::cout
+        << boost::get<0>(t) << '\n'
+        << boost::get<1>(t) << '\n'
+        << boost::get<2>(t) << '\n'
+        ;
+
+    return 0;
+}