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- /*!
- @file
- Forward declares `boost::hana::accessors`.
- @copyright Louis Dionne 2013-2017
- Distributed under the Boost Software License, Version 1.0.
- (See accompanying file LICENSE.md or copy at http://boost.org/LICENSE_1_0.txt)
- */
- #ifndef BOOST_HANA_FWD_ACCESSORS_HPP
- #define BOOST_HANA_FWD_ACCESSORS_HPP
- #include <boost/hana/config.hpp>
- #include <boost/hana/core/when.hpp>
- BOOST_HANA_NAMESPACE_BEGIN
- //! Returns a `Sequence` of pairs representing the accessors of the
- //! data structure.
- //! @ingroup group-Struct
- //!
- //! Given a `Struct` `S`, `accessors<S>()` is a `Sequence` of `Product`s
- //! where the first element of each pair is the "name" of a member of
- //! the `Struct`, and the second element of each pair is a function that
- //! can be used to access that member when given an object of the proper
- //! data type. As described in the global documentation for `Struct`, the
- //! accessor functions in this sequence must be move-independent.
- //!
- //!
- //! Example
- //! -------
- //! @include example/accessors.cpp
- #ifdef BOOST_HANA_DOXYGEN_INVOKED
- template <typename S>
- constexpr auto accessors = []() {
- return tag-dispatched;
- };
- #else
- template <typename S, typename = void>
- struct accessors_impl : accessors_impl<S, when<true>> { };
- template <typename S>
- struct accessors_t;
- template <typename S>
- constexpr accessors_t<S> accessors{};
- #endif
- BOOST_HANA_NAMESPACE_END
- #endif // !BOOST_HANA_FWD_ACCESSORS_HPP
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