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+/*!
+@file
+Forward declares `boost::hana::fuse`.
+
+@copyright Louis Dionne 2013-2016
+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_FUSE_HPP
+#define BOOST_HANA_FWD_FUSE_HPP
+
+#include <boost/hana/config.hpp>
+
+
+BOOST_HANA_NAMESPACE_BEGIN
+ //! Transform a function taking multiple arguments into a function that
+ //! can be called with a compile-time `Foldable`.
+ //! @ingroup group-Foldable
+ //!
+ //!
+ //! This function is provided for convenience as a different way of
+ //! calling `unpack`. Specifically, `fuse(f)` is a function such that
+ //! @code
+ //! fuse(f)(foldable) == unpack(foldable, f)
+ //! == f(x...)
+ //! @endcode
+ //! where `x...` are the elements in the foldable. This function is
+ //! useful when one wants to create a function that accepts a foldable
+ //! which is not known yet.
+ //!
+ //! @note
+ //! This function is not tag-dispatched; customize `unpack` instead.
+ //!
+ //!
+ //! Example
+ //! -------
+ //! @include example/fuse.cpp
+#ifdef BOOST_HANA_DOXYGEN_INVOKED
+ constexpr auto fuse = [](auto&& f) {
+ return [perfect-capture](auto&& xs) -> decltype(auto) {
+ return unpack(forwarded(xs), forwarded(f));
+ };
+ };
+#else
+ struct fuse_t {
+ template <typename F>
+ constexpr auto operator()(F&& f) const;
+ };
+
+ constexpr fuse_t fuse{};
+#endif
+BOOST_HANA_NAMESPACE_END
+
+#endif // !BOOST_HANA_FWD_FUSE_HPP