add boost on mac

macx64/include/boost/hana/cartesian_product.hpp

@@ -0,0 +1,113 @@
+/*!
+@file
+Defines `boost::hana::cartesian_product`.
+
+@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_CARTESIAN_PRODUCT_HPP
+#define BOOST_HANA_CARTESIAN_PRODUCT_HPP
+
+#include <boost/hana/fwd/cartesian_product.hpp>
+
+#include <boost/hana/at.hpp>
+#include <boost/hana/concept/sequence.hpp>
+#include <boost/hana/config.hpp>
+#include <boost/hana/core/dispatch.hpp>
+#include <boost/hana/core/make.hpp>
+#include <boost/hana/detail/array.hpp>
+#include <boost/hana/integral_constant.hpp>
+#include <boost/hana/length.hpp>
+#include <boost/hana/unpack.hpp>
+
+#include <cstddef>
+#include <utility>
+
+
+BOOST_HANA_NAMESPACE_BEGIN
+    //! @cond
+    template <typename Xs>
+    constexpr auto cartesian_product_t::operator()(Xs&& xs) const {
+        using S = typename hana::tag_of<Xs>::type;
+        using CartesianProduct = BOOST_HANA_DISPATCH_IF(
+            cartesian_product_impl<S>,
+            hana::Sequence<S>::value
+        );
+
+    #ifndef BOOST_HANA_CONFIG_DISABLE_CONCEPT_CHECKS
+        static_assert(hana::Sequence<S>::value,
+        "hana::cartesian_product(xs) requires 'xs' to be a Sequence");
+    #endif
+
+        return CartesianProduct::apply(static_cast<Xs&&>(xs));
+    }
+    //! @endcond
+
+    namespace detail {
+        template <std::size_t ...Lengths>
+        struct cartesian_product_indices {
+            static constexpr std::size_t total_length() {
+                std::size_t lengths[sizeof...(Lengths)] = {Lengths...};
+                std::size_t r = 1;
+                for (std::size_t len: lengths)
+                    r *= len;
+                return r;
+            }
+
+            static constexpr std::size_t length = total_length();
+
+            static constexpr auto indices_of(std::size_t i) {
+                constexpr std::size_t lengths[sizeof...(Lengths)] = {Lengths...};
+                constexpr std::size_t n = sizeof...(Lengths);
+                detail::array<std::size_t, n> result{};
+                for (std::size_t j = n; j--;) {
+                    result[j] = i % lengths[j];
+                    i /= lengths[j];
+                }
+                return result;
+            }
+
+            template <typename S, std::size_t n, std::size_t ...k, typename ...Xs>
+            static constexpr auto
+            product_element(std::index_sequence<k...>, Xs&& ...xs) {
+                constexpr auto indices = indices_of(n);
+                return hana::make<S>(hana::at_c<indices[k]>(xs)...);
+            }
+
+            template <typename S, std::size_t ...n, typename ...Xs>
+            static constexpr auto
+            create_product(std::index_sequence<n...>, Xs&& ...xs) {
+                return hana::make<S>(product_element<S, n>(
+                    std::make_index_sequence<sizeof...(Xs)>{}, xs...
+                )...);
+            }
+        };
+    }
+
+    // Credits: implementation adapted from http://github.com/alexk7/hel.
+    template <typename S, bool condition>
+    struct cartesian_product_impl<S, when<condition>> : default_ {
+        template <typename Xs>
+        static constexpr auto apply(Xs&& xs) {
+            return hana::unpack(static_cast<Xs&&>(xs), cartesian_product_impl{});
+        }
+
+        template <typename ...Xs>
+        constexpr auto operator()(Xs&& ...xs) const {
+            using indices = detail::cartesian_product_indices<
+                decltype(hana::length(xs))::value...
+            >;
+            return indices::template create_product<S>(
+                        std::make_index_sequence<indices::length>{},
+                        static_cast<Xs&&>(xs)...);
+        }
+
+        constexpr auto operator()() const {
+            return hana::make<S>();
+        }
+    };
+BOOST_HANA_NAMESPACE_END
+
+#endif // !BOOST_HANA_CARTESIAN_PRODUCT_HPP