Added thirdparty: boost library

thirdparty/include/boost/hana/find.hpp

@@ -0,0 +1,61 @@
+/*!
+@file
+Defines `boost::hana::find`.
+
+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_FIND_HPP
+#define BOOST_HANA_FIND_HPP
+
+#include <boost/hana/fwd/find.hpp>
+
+#include <boost/hana/concept/searchable.hpp>
+#include <boost/hana/config.hpp>
+#include <boost/hana/core/dispatch.hpp>
+#include <boost/hana/equal.hpp>
+#include <boost/hana/find_if.hpp>
+
+
+namespace boost { namespace hana {
+    //! @cond
+    template <typename Xs, typename Key>
+    constexpr auto find_t::operator()(Xs&& xs, Key const& key) const {
+        using S = typename hana::tag_of<Xs>::type;
+        using Find = BOOST_HANA_DISPATCH_IF(find_impl<S>,
+            hana::Searchable<S>::value
+        );
+
+    #ifndef BOOST_HANA_CONFIG_DISABLE_CONCEPT_CHECKS
+        static_assert(hana::Searchable<S>::value,
+        "hana::find(xs, key) requires 'xs' to be Searchable");
+    #endif
+
+        return Find::apply(static_cast<Xs&&>(xs), key);
+    }
+    //! @endcond
+
+    namespace detail {
+        template <typename T>
+        struct equal_to {
+            T const& t;
+            template <typename U>
+            constexpr auto operator()(U const& u) const {
+                return hana::equal(t, u);
+            }
+        };
+    }
+
+    template <typename S, bool condition>
+    struct find_impl<S, when<condition>> : default_ {
+        template <typename Xs, typename Key>
+        static constexpr auto apply(Xs&& xs, Key const& key) {
+            return hana::find_if(static_cast<Xs&&>(xs),
+                                 detail::equal_to<Key>{key});
+        }
+    };
+}} // end namespace boost::hana
+
+#endif // !BOOST_HANA_FIND_HPP