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diff --git a/src/boost/libs/spirit/example/qi/complex_number.cpp b/src/boost/libs/spirit/example/qi/complex_number.cpp
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+/*=============================================================================
+ Copyright (c) 2002-2010 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)
+=============================================================================*/
+///////////////////////////////////////////////////////////////////////////////
+//
+// A complex number micro parser.
+//
+// [ JDG May 10, 2002 ] spirit1
+// [ JDG May 9, 2007 ] spirit2
+//
+///////////////////////////////////////////////////////////////////////////////
+
+#include <boost/config/warning_disable.hpp>
+#include <boost/spirit/include/qi.hpp>
+#include <boost/spirit/include/phoenix_core.hpp>
+#include <boost/spirit/include/phoenix_operator.hpp>
+
+#include <iostream>
+#include <string>
+#include <complex>
+
+///////////////////////////////////////////////////////////////////////////////
+// Our complex number parser/compiler
+///////////////////////////////////////////////////////////////////////////////
+//[tutorial_complex_number
+namespace client
+{
+ template <typename Iterator>
+ bool parse_complex(Iterator first, Iterator last, std::complex<double>& c)
+ {
+ using boost::spirit::qi::double_;
+ using boost::spirit::qi::_1;
+ using boost::spirit::qi::phrase_parse;
+ using boost::spirit::ascii::space;
+ using boost::phoenix::ref;
+
+ double rN = 0.0;
+ double iN = 0.0;
+ bool r = phrase_parse(first, last,
+
+ // Begin grammar
+ (
+ '(' >> double_[ref(rN) = _1]
+ >> -(',' >> double_[ref(iN) = _1]) >> ')'
+ | double_[ref(rN) = _1]
+ ),
+ // End grammar
+
+ space);
+
+ if (!r || first != last) // fail if we did not get a full match
+ return false;
+ c = std::complex<double>(rN, iN);
+ return r;
+ }
+}
+//]
+
+////////////////////////////////////////////////////////////////////////////
+// Main program
+////////////////////////////////////////////////////////////////////////////
+int
+main()
+{
+ std::cout << "/////////////////////////////////////////////////////////\n\n";
+ std::cout << "\t\tA complex number micro parser for Spirit...\n\n";
+ std::cout << "/////////////////////////////////////////////////////////\n\n";
+
+ std::cout << "Give me a complex number of the form r or (r) or (r,i) \n";
+ std::cout << "Type [q or Q] to quit\n\n";
+
+ std::string str;
+ while (getline(std::cin, str))
+ {
+ if (str.empty() || str[0] == 'q' || str[0] == 'Q')
+ break;
+
+ std::complex<double> c;
+ if (client::parse_complex(str.begin(), str.end(), c))
+ {
+ std::cout << "-------------------------\n";
+ std::cout << "Parsing succeeded\n";
+ std::cout << "got: " << c << std::endl;
+ std::cout << "\n-------------------------\n";
+ }
+ else
+ {
+ std::cout << "-------------------------\n";
+ std::cout << "Parsing failed\n";
+ std::cout << "-------------------------\n";
+ }
+ }
+
+ std::cout << "Bye... :-) \n\n";
+ return 0;
+}
+
+