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+/*!
+@file
+Defines `boost::hana::replicate`.
+
+@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_REPLICATE_HPP
+#define BOOST_HANA_REPLICATE_HPP
+
+#include <boost/hana/fwd/replicate.hpp>
+
+#include <boost/hana/concept/integral_constant.hpp>
+#include <boost/hana/concept/monad_plus.hpp>
+#include <boost/hana/config.hpp>
+#include <boost/hana/core/dispatch.hpp>
+#include <boost/hana/core/make.hpp>
+#include <boost/hana/cycle.hpp>
+#include <boost/hana/lift.hpp>
+
+#include <cstddef>
+#include <utility>
+
+
+BOOST_HANA_NAMESPACE_BEGIN
+ template <typename M>
+ struct replicate_t {
+ #ifndef BOOST_HANA_CONFIG_DISABLE_CONCEPT_CHECKS
+ static_assert(hana::MonadPlus<M>::value,
+ "hana::replicate<M>(x, n) requires 'M' to be a MonadPlus");
+ #endif
+
+ template <typename X, typename N>
+ constexpr auto operator()(X&& x, N const& n) const {
+ using Replicate = BOOST_HANA_DISPATCH_IF(replicate_impl<M>,
+ hana::MonadPlus<M>::value &&
+ hana::IntegralConstant<N>::value
+ );
+
+ #ifndef BOOST_HANA_CONFIG_DISABLE_CONCEPT_CHECKS
+ static_assert(hana::IntegralConstant<N>::value,
+ "hana::replicate<M>(x, n) requires 'n' to be an IntegralConstant");
+ #endif
+
+ return Replicate::apply(static_cast<X&&>(x), n);
+ }
+ };
+
+ template <typename M, bool condition>
+ struct replicate_impl<M, when<condition>> : default_ {
+ template <typename X, typename N>
+ static constexpr auto apply(X&& x, N const& n) {
+ return hana::cycle(hana::lift<M>(static_cast<X&&>(x)), n);
+ }
+ };
+
+ template <typename S>
+ struct replicate_impl<S, when<Sequence<S>::value>> {
+ template <typename X, std::size_t ...i>
+ static constexpr auto replicate_helper(X&& x, std::index_sequence<i...>)
+ { return hana::make<S>(((void)i, x)...); }
+
+ template <typename X, typename N>
+ static constexpr auto apply(X&& x, N const&) {
+ constexpr std::size_t n = N::value;
+ return replicate_helper(static_cast<X&&>(x),
+ std::make_index_sequence<n>{});
+ }
+ };
+BOOST_HANA_NAMESPACE_END
+
+#endif // !BOOST_HANA_REPLICATE_HPP