spirit/example/x3/attributes/tuple.cpp

51 lines
1.5 KiB
C++

/*=============================================================================
Copyright (c) 2019 Tom Tan
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 <boost/config/warning_disable.hpp>
#include <boost/spirit/home/x3.hpp>
#include <boost/fusion/adapted/std_tuple.hpp>
#include <iostream>
#include <tuple>
#include <string>
//
// X3 does not support more than one attribute anymore in the parse function,
// this example show how to wrap multiple attributes into one leveraging std::tuple.
//
std::tuple<uint32_t, uint32_t, uint32_t> parse_message_prefix_revision(const std::string &s)
{
namespace x3 = boost::spirit::x3;
auto const uint_3_digits = x3::uint_parser<std::uint32_t, 10, 3, 3>{};
auto const uint_4_digits = x3::uint_parser<std::uint32_t, 10, 4, 4>{};
auto iter = s.cbegin();
auto end_iter = s.cend();
std::tuple<uint32_t, uint32_t, uint32_t> length_id_revision;
x3::parse(iter, end_iter,
uint_4_digits >> uint_4_digits >> uint_3_digits,
length_id_revision);
return length_id_revision;
}
int main()
{
std::string s = "00200060001";
std::cout << "parsing " << s << '\n';
auto [len, id, rev] = parse_message_prefix_revision(s);
std::cout << "length = " << len << '\n'
<< "id = " << id << '\n'
<< "revision =" << rev;
}