ceph/src/boost/libs/spirit/test/lex/lexer_state_switcher.cpp

   1 //  Copyright (c) 2001-2011 Hartmut Kaiser
   2 //
   3 //  Distributed under the Boost Software License, Version 1.0. (See accompanying
   4 //  file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
   5
   6 #include <boost/mpl/print.hpp>
   7 #include <boost/detail/lightweight_test.hpp>
   8 #include <boost/spirit/include/phoenix_object.hpp>
   9 #include <boost/spirit/include/phoenix_operator.hpp>
  10 #include <boost/spirit/include/lex_lexertl.hpp>
  11
  12 ///////////////////////////////////////////////////////////////////////////////
  13 //  Token definition
  14 ///////////////////////////////////////////////////////////////////////////////
  15 template <typename Lexer>
  16 struct switch_state_tokens : boost::spirit::lex::lexer<Lexer>
  17 {
  18     // define tokens and associate them with the lexer
  19     switch_state_tokens()
  20     {
  21         namespace phoenix = boost::phoenix;
  22         using boost::spirit::lex::_state;
  23
  24         identifier = "[a-zA-Z_][a-zA-Z0-9_]*";
  25         this->self = identifier [ phoenix::ref(state_) = _state ];
  26
  27         integer = "[0-9]+";
  28         this->self("INT") = integer [ _state = "INITIAL" ];
  29     }
  30
  31     std::string state_;
  32     boost::spirit::lex::token_def<> identifier, integer;
  33 };
  34
  35 ///////////////////////////////////////////////////////////////////////////////
  36 int main()
  37 {
  38     using namespace boost::spirit;
  39     using namespace boost::spirit::lex;
  40
  41     typedef std::string::iterator base_iterator_type;
  42     typedef boost::spirit::lex::lexertl::token<base_iterator_type> token_type;
  43     typedef boost::spirit::lex::lexertl::actor_lexer<token_type> lexer_type;
  44
  45     {
  46         switch_state_tokens<lexer_type> lex;
  47
  48         {
  49             // verify whether using _state as an rvalue works
  50             std::string input("abc123");
  51             base_iterator_type first = input.begin();
  52             BOOST_TEST(boost::spirit::lex::tokenize(first, input.end(), lex) &&
  53                 lex.state_ == "INITIAL");
  54         }
  55         {
  56             // verify whether using _state as an lvalue works
  57             std::string input("123abc123");
  58             base_iterator_type first = input.begin();
  59             BOOST_TEST(boost::spirit::lex::tokenize(first, input.end(), lex, "INT") &&
  60                 lex.state_ == "INITIAL");
  61         }
  62     }
  63
  64     return boost::report_errors();
  65 }
  66