home/support/sequence_base_id.hpp

0001 /*=============================================================================
0002     Copyright (c) 2001-2011 Joel de Guzman
0003
0004     Distributed under the Boost Software License, Version 1.0. (See accompanying
0005     file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
0006 =============================================================================*/
0007 #ifndef BOOST_SPIRIT_SUPPORT_SEQUENCE_BASE_ID_HPP
0008 #define BOOST_SPIRIT_SUPPORT_SEQUENCE_BASE_ID_HPP
0009
0010 #if defined(_MSC_VER)
0011 #pragma once
0012 #endif
0013
0014 #include <boost/mpl/has_xxx.hpp>
0015 #include <boost/utility/enable_if.hpp>
0016 #include <boost/spirit/home/support/attributes.hpp>
0017
0018 namespace boost { namespace spirit { namespace traits
0019 {
0020     namespace detail
0021     {
0022         BOOST_MPL_HAS_XXX_TRAIT_DEF(sequence_base_id)
0023     }
0024
0025     // We specialize this for sequences (see support/attributes.hpp).
0026     // For sequences, we only wrap the attribute in a tuple IFF
0027     // it is not already a fusion tuple.
0028     //
0029     // Note: in the comment above, "sequence" is a spirit sequence
0030     // component (parser or generator), and a tuple is a fusion sequence
0031     // (to avoid terminology confusion).
0032     template <typename Derived, typename Attribute>
0033     struct pass_attribute<Derived, Attribute,
0034         typename enable_if<detail::has_sequence_base_id<Derived> >::type>
0035       : wrap_if_not_tuple<Attribute> {};
0036
0037 }}}
0038
0039 #endif