Added thirdparty: boost library

thirdparty/include/boost/hana/symmetric_difference.hpp

@@ -0,0 +1,46 @@
+/*!
+@file
+Defines `boost::hana::symmetric_difference`.
+
+Copyright Louis Dionne 2013-2022
+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_SYMMETRIC_DIFFERENCE_HPP
+#define BOOST_HANA_SYMMETRIC_DIFFERENCE_HPP
+
+#include <boost/hana/fwd/symmetric_difference.hpp>
+
+#include <boost/hana/config.hpp>
+#include <boost/hana/core/dispatch.hpp>
+#include <boost/hana/difference.hpp>
+#include <boost/hana/union.hpp>
+
+
+namespace boost { namespace hana {
+    //! @cond
+    template <typename Xs, typename Ys>
+    constexpr auto symmetric_difference_t::operator()(Xs&& xs, Ys&& ys) const {
+        using S = typename hana::tag_of<Xs>::type;
+        using SymmetricDifference = BOOST_HANA_DISPATCH_IF(symmetric_difference_impl<S>,
+            true
+        );
+
+        return SymmetricDifference::apply(static_cast<Xs&&>(xs), static_cast<Ys&&>(ys));
+    }
+    //! @endcond
+
+    template <typename S, bool condition>
+    struct symmetric_difference_impl<S, when<condition>> : default_ {
+        template <typename Xs, typename Ys>
+        static constexpr auto apply(Xs&& xs, Ys&& ys) {
+            return hana::union_(
+                hana::difference(xs, ys),
+                hana::difference(ys, xs)
+            );
+        }
+    };
+}} // end namespace boost::hana
+
+#endif // !BOOST_HANA_SYMMETRIC_DIFFERENCE_HPP