libs/spirit/example/support/multi_pass.cpp
// 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)
#include <iostream>
#include <fstream>
#include <vector>
#include <boost/spirit/include/qi.hpp>
#include <boost/spirit/include/support_multi_pass.hpp>
///////////////////////////////////////////////////////////////////////////////
///////////////////////////////////////////////////////////////////////////////
//[tutorial_multi_pass
int main()
{
namespace spirit = boost::spirit;
using spirit::ascii::space;
using spirit::ascii::char_;
using spirit::qi::double_;
using spirit::qi::eol;
std::ifstream in("multi_pass.txt"); // we get our input from this file
if (!in.is_open()) {
std::cout << "Could not open input file: 'multi_pass.txt'" << std::endl;
return -1;
}
typedef std::istreambuf_iterator<char> base_iterator_type;
spirit::multi_pass<base_iterator_type> first =
spirit::make_default_multi_pass(base_iterator_type(in));
std::vector<double> v;
bool result = spirit::qi::phrase_parse(first
, spirit::make_default_multi_pass(base_iterator_type())
, double_ >> *(',' >> double_) // recognize list of doubles
, space | '#' >> *(char_ - eol) >> eol // comment skipper
, v); // data read from file
if (!result) {
std::cout << "Failed parsing input file!" << std::endl;
return -2;
}
std::cout << "Successfully parsed input file!" << std::endl;
return 0;
}
//]