1 2 // Copyright 2018 Peter Dimov. 3 // 4 // Distributed under the Boost Software License, Version 1.0. 5 // 6 // See accompanying file LICENSE_1_0.txt or copy at 7 // http://www.boost.org/LICENSE_1_0.txt 8 9 #include <boost/wave.hpp> 10 #include <boost/wave/cpplexer/cpp_lex_token.hpp> 11 #include <boost/wave/cpplexer/cpp_lex_iterator.hpp> 12 #include <iostream> 13 main()14int main() 15 { 16 std::string input( 17 "#if 0\n" 18 "6.28\n" 19 "#else\n" 20 "3.14\n" 21 "#endif\n" 22 ); 23 24 try 25 { 26 typedef boost::wave::cpplexer::lex_token<> token_type; 27 typedef boost::wave::cpplexer::lex_iterator<token_type> lex_iterator_type; 28 typedef boost::wave::context<std::string::iterator, lex_iterator_type> context_type; 29 30 context_type ctx( input.begin(), input.end(), "input.cpp" ); 31 32 for( context_type::iterator_type first = ctx.begin(), last = ctx.end(); first != last; ++first ) 33 { 34 std::cout << first->get_value(); 35 } 36 37 return 0; 38 } 39 catch( boost::wave::cpp_exception const & x ) 40 { 41 std::cerr << x.file_name() << "(" << x.line_no() << "): " << x.description() << std::endl; 42 return 1; 43 } 44 catch( std::exception const & x ) 45 { 46 std::cerr << "Exception: " << x.what() << std::endl; 47 return 2; 48 } 49 } 50