1 /*=============================================================================
2 Boost.Wave: A Standard compliant C++ preprocessor library
3
4 http://www.boost.org/
5
6 Copyright (c) 2001-2012 Hartmut Kaiser. Distributed under the Boost
7 Software License, Version 1.0. (See accompanying file
8 LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
9 =============================================================================*/
10
11 #include <iostream>
12 #include <fstream>
13 #include <string>
14 #include <vector>
15
16 ///////////////////////////////////////////////////////////////////////////////
17 // Include Wave itself
18 #include <boost/wave.hpp>
19
20 ///////////////////////////////////////////////////////////////////////////////
21 // Include the lexer stuff
22 #include <boost/wave/cpplexer/cpp_lex_token.hpp> // token class
23 #include <boost/wave/cpplexer/cpp_lex_iterator.hpp> // lexer class
24
25 ///////////////////////////////////////////////////////////////////////////////
26 // main entry point
main(int argc,char * argv[])27 int main(int argc, char *argv[])
28 {
29 if (2 != argc) {
30 std::cerr << "Usage: quick_start infile" << std::endl;
31 return -1;
32 }
33
34 // current file position is saved for exception handling
35 boost::wave::util::file_position_type current_position;
36
37 try {
38 //[quick_start_main
39 // The following preprocesses the input file given by argv[1].
40 // Open and read in the specified input file.
41 std::ifstream instream(argv[1]);
42 std::string instring;
43
44 if (!instream.is_open()) {
45 std::cerr << "Could not open input file: " << argv[1] << std::endl;
46 return -2;
47 }
48 instream.unsetf(std::ios::skipws);
49 instring = std::string(std::istreambuf_iterator<char>(instream.rdbuf()),
50 std::istreambuf_iterator<char>());
51
52 // This token type is one of the central types used throughout the library.
53 // It is a template parameter to some of the public classes and instances
54 // of this type are returned from the iterators.
55 typedef boost::wave::cpplexer::lex_token<> token_type;
56
57 // The template boost::wave::cpplexer::lex_iterator<> is the lexer type to
58 // to use as the token source for the preprocessing engine. It is
59 // parametrized with the token type.
60 typedef boost::wave::cpplexer::lex_iterator<token_type> lex_iterator_type;
61
62 // This is the resulting context type. The first template parameter should
63 // match the iterator type used during construction of the context
64 // instance (see below). It is the type of the underlying input stream.
65 typedef boost::wave::context<std::string::iterator, lex_iterator_type>
66 context_type;
67
68 // The preprocessor iterator shouldn't be constructed directly. It is
69 // generated through a wave::context<> object. This wave:context<> object
70 // is additionally used to initialize and define different parameters of
71 // the actual preprocessing (not done here).
72 //
73 // The preprocessing of the input stream is done on the fly behind the
74 // scenes during iteration over the range of context_type::iterator_type
75 // instances.
76 context_type ctx (instring.begin(), instring.end(), argv[1]);
77
78 // Get the preprocessor iterators and use them to generate the token
79 // sequence.
80 context_type::iterator_type first = ctx.begin();
81 context_type::iterator_type last = ctx.end();
82
83 // The input stream is preprocessed for you while iterating over the range
84 // [first, last). The dereferenced iterator returns tokens holding
85 // information about the preprocessed input stream, such as token type,
86 // token value, and position.
87 while (first != last) {
88 current_position = (*first).get_position();
89 std::cout << (*first).get_value();
90 ++first;
91 }
92 //]
93 }
94 catch (boost::wave::cpp_exception const& e) {
95 // some preprocessing error
96 std::cerr
97 << e.file_name() << "(" << e.line_no() << "): "
98 << e.description() << std::endl;
99 return 2;
100 }
101 catch (std::exception const& e) {
102 // use last recognized token to retrieve the error position
103 std::cerr
104 << current_position.get_file()
105 << "(" << current_position.get_line() << "): "
106 << "exception caught: " << e.what()
107 << std::endl;
108 return 3;
109 }
110 catch (...) {
111 // use last recognized token to retrieve the error position
112 std::cerr
113 << current_position.get_file()
114 << "(" << current_position.get_line() << "): "
115 << "unexpected exception caught." << std::endl;
116 return 4;
117 }
118 return 0;
119 }
120