| 1 | // Copyright (c) 2001-2010 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 <iostream> |
| 7 | #include <fstream> |
| 8 | #include <vector> |
| 9 | |
| 10 | #include <boost/spirit/include/qi.hpp> |
| 11 | #include <boost/spirit/include/support_multi_pass.hpp> |
| 12 | |
| 13 | /////////////////////////////////////////////////////////////////////////////// |
| 14 | |
| 15 | /////////////////////////////////////////////////////////////////////////////// |
| 16 | //[tutorial_multi_pass |
| 17 | int main() |
| 18 | { |
| 19 | namespace spirit = boost::spirit; |
| 20 | using spirit::ascii::space; |
| 21 | using spirit::ascii::char_; |
| 22 | using spirit::qi::double_; |
| 23 | using spirit::qi::eol; |
| 24 | |
| 25 | std::ifstream in("multi_pass.txt"); // we get our input from this file |
| 26 | if (!in.is_open()) { |
| 27 | std::cout << "Could not open input file: 'multi_pass.txt'"<< std::endl; |
| 28 | return -1; |
| 29 | } |
| 30 | |
| 31 | typedef std::istreambuf_iterator<char> base_iterator_type; |
| 32 | spirit::multi_pass<base_iterator_type> first = |
| 33 | spirit::make_default_multi_pass(i: base_iterator_type(in)); |
| 34 | |
| 35 | std::vector<double> v; |
| 36 | bool result = spirit::qi::phrase_parse(first |
| 37 | , last: spirit::make_default_multi_pass(i: base_iterator_type()) |
| 38 | , expr: double_ >> *(',' >> double_) // recognize list of doubles |
| 39 | , skipper: space | '#' >> *(char_ - eol) >> eol // comment skipper |
| 40 | , attr&: v); // data read from file |
| 41 | |
| 42 | if (!result) { |
| 43 | std::cout << "Failed parsing input file!"<< std::endl; |
| 44 | return -2; |
| 45 | } |
| 46 | |
| 47 | std::cout << "Successfully parsed input file!"<< std::endl; |
| 48 | return 0; |
| 49 | } |
| 50 | //] |
| 51 |