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+/*=============================================================================
+ Copyright (c) 2015 Paul Fultz II
+ rotate.h
+ 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)
+==============================================================================*/
+
+#ifndef BOOST_HOF_GUARD_ROTATE_H
+#define BOOST_HOF_GUARD_ROTATE_H
+
+/// rotate
+/// ====
+///
+/// Description
+/// -----------
+///
+/// The `rotate` function adaptor moves the first parameter to the last
+/// parameter.
+///
+/// Synopsis
+/// --------
+///
+/// template<class F>
+/// rotate_adaptor<F> rotate(F f);
+///
+/// Semantics
+/// ---------
+///
+/// assert(rotate(f)(x, xs...) == f(xs..., x));
+///
+/// Requirements
+/// ------------
+///
+/// F must be:
+///
+/// * [ConstInvocable](ConstInvocable)
+/// * MoveConstructible
+///
+/// Example
+/// -------
+///
+/// #include <boost/hof.hpp>
+/// #include <cassert>
+///
+/// int main() {
+/// int r = boost::hof::rotate(boost::hof::_ - boost::hof::_)(2, 5);
+/// assert(r == 3);
+/// }
+///
+
+#include <boost/hof/detail/result_of.hpp>
+#include <boost/hof/reveal.hpp>
+#include <boost/hof/detail/make.hpp>
+#include <boost/hof/detail/static_const_var.hpp>
+
+namespace boost { namespace hof {
+
+template<class F>
+struct rotate_adaptor : detail::callable_base<F>
+{
+ typedef rotate_adaptor fit_rewritable1_tag;
+ BOOST_HOF_INHERIT_CONSTRUCTOR(rotate_adaptor, detail::callable_base<F>);
+
+ template<class... Ts>
+ constexpr const detail::callable_base<F>& base_function(Ts&&... xs) const noexcept
+ {
+ return boost::hof::always_ref(*this)(xs...);
+ }
+
+ struct rotate_failure
+ {
+ template<class Failure>
+ struct apply
+ {
+ template<class T, class... Ts>
+ struct of
+ : Failure::template of<Ts..., T>
+ {};
+ };
+ };
+
+ struct failure
+ : failure_map<rotate_failure, detail::callable_base<F>>
+ {};
+
+ BOOST_HOF_RETURNS_CLASS(rotate_adaptor);
+
+ template<class T, class... Ts>
+ constexpr BOOST_HOF_SFINAE_RESULT(const detail::callable_base<F>&, id_<Ts>..., id_<T>)
+ operator()(T&& x, Ts&&... xs) const BOOST_HOF_SFINAE_RETURNS
+ (
+ (BOOST_HOF_MANGLE_CAST(const detail::callable_base<F>&)(BOOST_HOF_CONST_THIS->base_function(xs...)))
+ (BOOST_HOF_FORWARD(Ts)(xs)..., BOOST_HOF_FORWARD(T)(x))
+ );
+};
+
+BOOST_HOF_DECLARE_STATIC_VAR(rotate, detail::make<rotate_adaptor>);
+
+}} // namespace boost::hof
+
+#endif