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diff --git a/src/boost/libs/spirit/example/lex/strip_comments.cpp b/src/boost/libs/spirit/example/lex/strip_comments.cpp
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+//  Copyright (c) 2001-2010 Hartmut Kaiser
+// 
+//  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)
+
+//  This example is the equivalent to the following lex program:
+//
+//       %{
+//       /* INITIAL is the default start state.  COMMENT is our new  */
+//       /* state where we remove comments.                          */
+//       %}
+// 
+//       %s COMMENT
+//       %%
+//       <INITIAL>"//".*    ;
+//       <INITIAL>"/*"      BEGIN COMMENT; 
+//       <INITIAL>.         ECHO;
+//       <INITIAL>[\n]      ECHO;
+//       <COMMENT>"*/"      BEGIN INITIAL;
+//       <COMMENT>.         ;
+//       <COMMENT>[\n]      ;
+//       %%
+// 
+//       main() 
+//       {
+//         yylex();
+//       }
+//
+//  Its purpose is to strip comments out of C code.
+//
+//  Additionally this example demonstrates the use of lexer states to structure
+//  the lexer definition.
+
+// #define BOOST_SPIRIT_LEXERTL_DEBUG
+
+#include <boost/config/warning_disable.hpp>
+#include <boost/spirit/include/qi.hpp>
+#include <boost/spirit/include/lex_lexertl.hpp>
+#include <boost/spirit/include/phoenix_operator.hpp>
+#include <boost/spirit/include/phoenix_container.hpp>
+
+#include <iostream>
+#include <string>
+
+#include "example.hpp"
+
+using namespace boost::spirit;
+
+///////////////////////////////////////////////////////////////////////////////
+//  Token definition: We use the lexertl based lexer engine as the underlying 
+//                    lexer type.
+///////////////////////////////////////////////////////////////////////////////
+enum tokenids 
+{
+    IDANY = lex::min_token_id + 10
+};
+
+template <typename Lexer>
+struct strip_comments_tokens : lex::lexer<Lexer>
+{
+    strip_comments_tokens() 
+      : strip_comments_tokens::base_type(lex::match_flags::match_default)
+    {
+        // define tokens and associate them with the lexer
+        cppcomment = "\"//\"[^\n]*";    // '//[^\n]*'
+        ccomment = "\"/*\"";            // '/*'
+        endcomment = "\"*/\"";          // '*/'
+
+        // The following tokens are associated with the default lexer state 
+        // (the "INITIAL" state). Specifying 'INITIAL' as a lexer state is 
+        // strictly optional.
+        this->self.add
+            (cppcomment)    // no explicit token id is associated
+            (ccomment)
+            (".", IDANY)    // IDANY is the token id associated with this token 
+                            // definition
+        ;
+
+        // The following tokens are associated with the lexer state "COMMENT".
+        // We switch lexer states from inside the parsing process using the 
+        // in_state("COMMENT")[] parser component as shown below.
+        this->self("COMMENT").add
+            (endcomment)
+            (".", IDANY)
+        ;
+    }
+
+    lex::token_def<> cppcomment, ccomment, endcomment;
+};
+
+///////////////////////////////////////////////////////////////////////////////
+//  Grammar definition
+///////////////////////////////////////////////////////////////////////////////
+template <typename Iterator>
+struct strip_comments_grammar : qi::grammar<Iterator>
+{
+    template <typename TokenDef>
+    strip_comments_grammar(TokenDef const& tok)
+      : strip_comments_grammar::base_type(start)
+    {
+        // The in_state("COMMENT")[...] parser component switches the lexer 
+        // state to be 'COMMENT' during the matching of the embedded parser.
+        start =  *(   tok.ccomment 
+                      >>  qi::in_state("COMMENT") 
+                          [
+                              // the lexer is in the 'COMMENT' state during
+                              // matching of the following parser components
+                              *token(IDANY) >> tok.endcomment 
+                          ]
+                  |   tok.cppcomment
+                  |   qi::token(IDANY)   [ std::cout << _1 ]
+                  )
+              ;
+    }
+
+    qi::rule<Iterator> start;
+};
+
+///////////////////////////////////////////////////////////////////////////////
+int main(int argc, char* argv[])
+{
+    // iterator type used to expose the underlying input stream
+    typedef std::string::iterator base_iterator_type;
+
+    // lexer type
+    typedef 
+        lex::lexertl::lexer<lex::lexertl::token<base_iterator_type> > 
+    lexer_type;
+
+    // iterator type exposed by the lexer 
+    typedef strip_comments_tokens<lexer_type>::iterator_type iterator_type;
+
+    // now we use the types defined above to create the lexer and grammar
+    // object instances needed to invoke the parsing process
+    strip_comments_tokens<lexer_type> strip_comments;           // Our lexer
+    strip_comments_grammar<iterator_type> g (strip_comments);   // Our parser 
+
+    // Parsing is done based on the token stream, not the character 
+    // stream read from the input.
+    std::string str (read_from_file(1 == argc ? "strip_comments.input" : argv[1]));
+    base_iterator_type first = str.begin();
+
+    bool r = lex::tokenize_and_parse(first, str.end(), strip_comments, g);
+
+    if (r) {
+        std::cout << "-------------------------\n";
+        std::cout << "Parsing succeeded\n";
+        std::cout << "-------------------------\n";
+    }
+    else {
+        std::string rest(first, str.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;
+}
+
+
+