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- /*=============================================================================
- Copyright (c) 2001-2014 Joel de Guzman
- http://spirit.sourceforge.net/
- 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)
- =============================================================================*/
- #if !defined(BOOST_SPIRIT_X3_IS_VARIANT_JAN_10_2012_0823AM)
- #define BOOST_SPIRIT_X3_IS_VARIANT_JAN_10_2012_0823AM
- #include <boost/variant.hpp>
- #include <boost/mpl/has_xxx.hpp>
- #include <boost/mpl/bool.hpp>
- namespace boost { namespace spirit { namespace x3 { namespace traits
- {
- namespace detail
- {
- // By declaring a nested struct in your class/struct, you tell
- // spirit that it is regarded as a variant type. The minimum
- // required interface for such a variant is that it has constructors
- // for various types supported by your variant and a typedef 'types'
- // which is an mpl sequence of the contained types.
- //
- // This is an intrusive interface. For a non-intrusive interface,
- // use the is_variant trait.
- BOOST_MPL_HAS_XXX_TRAIT_DEF(adapted_variant_tag)
- }
- template <typename T, typename Enable = void>
- struct is_variant
- : detail::has_adapted_variant_tag<T>
- {};
- template <BOOST_VARIANT_ENUM_PARAMS(typename T)>
- struct is_variant<boost::variant<BOOST_VARIANT_ENUM_PARAMS(T)>>
- : mpl::true_
- {};
- }}}}
- #endif
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