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// Copyright (c) 2009 Erik Bryan
// Copyright (c) 2007-2010 Hartmut Kaiser
//
// Distributed under the Boost Software License, Version 1.0. (See accompanying
// file licence_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
#include <string>
#include <vector>
#include <boost/array.hpp>
#include <boost/spirit/include/qi.hpp>
namespace qi = boost::spirit::qi;
namespace ascii = boost::spirit::ascii;
///////////////////////////////////////////////////////////////////////////////
// create a wrapper holding the boost::array and a current insertion point
namespace client
{
namespace detail
{
template <typename T>
struct adapt_array;
template <typename T, std::size_t N>
struct adapt_array<boost::array<T, N> >
{
typedef boost::array<T, N> array_type;
adapt_array(array_type& arr)
: arr_(arr), current_(0) {}
// expose a push_back function compatible with std containers
bool push_back(typename array_type::value_type const& val)
{
// if the array is full, we need to bail out
// returning false will fail the parse
if (current_ >= N)
return false;
arr_[current_++] = val;
return true;
}
array_type& arr_;
std::size_t current_;
};
}
namespace result_of
{
template <typename T>
struct adapt_array;
template <typename T, std::size_t N>
struct adapt_array<boost::array<T, N> >
{
typedef detail::adapt_array<boost::array<T, N> > type;
};
}
template <typename T, std::size_t N>
inline detail::adapt_array<boost::array<T, N> >
adapt_array(boost::array<T, N>& arr)
{
return detail::adapt_array<boost::array<T, N> >(arr);
}
}
///////////////////////////////////////////////////////////////////////////////
// specialize Spirit's container specific customization points for our adaptor
namespace boost { namespace spirit { namespace traits
{
template <typename T, std::size_t N>
struct is_container<client::detail::adapt_array<boost::array<T, N> > >
: boost::mpl::true_
{};
template <typename T, std::size_t N>
struct container_value<client::detail::adapt_array<boost::array<T, N> > >
{
typedef T type; // value type of container
};
template <typename T, std::size_t N>
struct push_back_container<
client::detail::adapt_array<boost::array<T, N> >, T>
{
static bool call(client::detail::adapt_array<boost::array<T, N> >& c
, T const& val)
{
return c.push_back(val);
}
};
}}}
int main()
{
typedef std::string::const_iterator iterator_type;
typedef boost::array<int, 2> array_type;
typedef client::result_of::adapt_array<array_type>::type adapted_type;
array_type arr;
std::string str = "1 2";
iterator_type iter = str.begin();
iterator_type end = str.end();
qi::rule<iterator_type, adapted_type(), ascii::space_type> r = *qi::int_;
adapted_type attr = client::adapt_array(arr);
bool result = qi::phrase_parse(iter, end, r, ascii::space, attr);
if (result)
std::cout << "Parsed: " << arr[0] << ", " << arr[1] << std::endl;
return 0;
}
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