| 1234567891011121314151617181920212223242526272829303132 | /*!@fileForward declares `boost::hana::erase_key`.@copyright Louis Dionne 2013-2017Distributed 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_ERASE_KEY_HPP#define BOOST_HANA_FWD_ERASE_KEY_HPP#include <boost/hana/config.hpp>#include <boost/hana/core/when.hpp>BOOST_HANA_NAMESPACE_BEGIN    // Note: This function is documented per datatype/concept only.    //! @cond    template <typename T, typename = void>    struct erase_key_impl : erase_key_impl<T, when<true>> { };    //! @endcond    struct erase_key_t {        template <typename Set, typename ...Args>        constexpr decltype(auto) operator()(Set&& set, Args&& ...args) const;    };    constexpr erase_key_t erase_key{};BOOST_HANA_NAMESPACE_END#endif // !BOOST_HANA_FWD_ERASE_KEY_HPP
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