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diff --git a/src/boost/libs/spirit/example/x3/calc/calc1.cpp b/src/boost/libs/spirit/example/x3/calc/calc1.cpp
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+++ b/src/boost/libs/spirit/example/x3/calc/calc1.cpp
@@ -0,0 +1,123 @@
+/*=============================================================================
+    Copyright (c) 2001-2014 Joel de Guzman
+
+    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)
+=============================================================================*/
+///////////////////////////////////////////////////////////////////////////////
+//
+//  Plain calculator example demonstrating the grammar. The parser is a
+//  syntax checker only and does not do any semantic evaluation.
+//
+//  [ JDG May 10, 2002 ]        spirit 1
+//  [ JDG March 4, 2007 ]       spirit 2
+//  [ JDG February 21, 2011 ]   spirit 2.5
+//  [ JDG June 6, 2014 ]        spirit x3
+//
+///////////////////////////////////////////////////////////////////////////////
+
+#include <boost/config/warning_disable.hpp>
+#include <boost/spirit/home/x3.hpp>
+#include <boost/spirit/home/x3/support/ast/variant.hpp>
+#include <boost/fusion/include/adapt_struct.hpp>
+
+#include <iostream>
+#include <string>
+#include <list>
+#include <numeric>
+
+namespace x3 = boost::spirit::x3;
+
+namespace client
+{
+    ///////////////////////////////////////////////////////////////////////////////
+    //  The calculator grammar
+    ///////////////////////////////////////////////////////////////////////////////
+    namespace calculator_grammar
+    {
+        using x3::uint_;
+        using x3::char_;
+
+        x3::rule<class expression> const expression("expression");
+        x3::rule<class term> const term("term");
+        x3::rule<class factor> const factor("factor");
+
+        auto const expression_def =
+            term
+            >> *(   ('+' >> term)
+                |   ('-' >> term)
+                )
+            ;
+
+        auto const term_def =
+            factor
+            >> *(   ('*' >> factor)
+                |   ('/' >> factor)
+                )
+            ;
+
+        auto const factor_def =
+                uint_
+            |   '(' >> expression >> ')'
+            |   ('-' >> factor)
+            |   ('+' >> factor)
+            ;
+
+        BOOST_SPIRIT_DEFINE(
+            expression
+          , term
+          , factor
+        );
+
+        auto calculator = expression;
+    }
+
+    using calculator_grammar::calculator;
+
+}
+
+///////////////////////////////////////////////////////////////////////////////
+//  Main program
+///////////////////////////////////////////////////////////////////////////////
+int
+main()
+{
+    std::cout << "/////////////////////////////////////////////////////////\n\n";
+    std::cout << "Expression parser...\n\n";
+    std::cout << "/////////////////////////////////////////////////////////\n\n";
+    std::cout << "Type an expression...or [q or Q] to quit\n\n";
+
+    typedef std::string::const_iterator iterator_type;
+
+    std::string str;
+    while (std::getline(std::cin, str))
+    {
+        if (str.empty() || str[0] == 'q' || str[0] == 'Q')
+            break;
+
+        auto& calc = client::calculator;    // Our grammar
+
+        iterator_type iter = str.begin();
+        iterator_type end = str.end();
+        boost::spirit::x3::ascii::space_type space;
+        bool r = phrase_parse(iter, end, calc, space);
+
+        if (r && iter == end)
+        {
+            std::cout << "-------------------------\n";
+            std::cout << "Parsing succeeded\n";
+            std::cout << "-------------------------\n";
+        }
+        else
+        {
+            std::string rest(iter, end);
+            std::cout << "-------------------------\n";
+            std::cout << "Parsing failed\n";
+            std::cout << "stopped at: \"" << rest << "\"\n";
+            std::cout << "-------------------------\n";
+        }
+    }
+
+    std::cout << "Bye... :-) \n\n";
+    return 0;
+}