stabilize build system: depends, installer, boost/bdb fixes, cross targets groundwork

2026-02-24 18:38:47 +00:00
parent da8c28aaeb
commit 65cb2619a7
13106 changed files with 2484322 additions and 1804 deletions
@@ -0,0 +1,76 @@
+/*!
+@file
+Defines `boost::hana::intersperse`.
+
+@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_INTERSPERSE_HPP
+#define BOOST_HANA_INTERSPERSE_HPP
+
+#include <boost/hana/fwd/intersperse.hpp>
+
+#include <boost/hana/at.hpp>
+#include <boost/hana/bool.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/length.hpp>
+
+#include <cstddef>
+#include <utility>
+
+
+BOOST_HANA_NAMESPACE_BEGIN
+    //! @cond
+    template <typename Xs, typename Z>
+    constexpr auto intersperse_t::operator()(Xs&& xs, Z&& z) const {
+        using S = typename hana::tag_of<Xs>::type;
+        using Intersperse = BOOST_HANA_DISPATCH_IF(intersperse_impl<S>,
+            hana::Sequence<S>::value
+        );
+
+    #ifndef BOOST_HANA_CONFIG_DISABLE_CONCEPT_CHECKS
+        static_assert(hana::Sequence<S>::value,
+        "hana::intersperse(xs, z) requires 'xs' to be a Sequence");
+    #endif
+
+        return Intersperse::apply(static_cast<Xs&&>(xs), static_cast<Z&&>(z));
+    }
+    //! @endcond
+
+    template <typename S, bool condition>
+    struct intersperse_impl<S, when<condition>> : default_ {
+        template <std::size_t i, typename Xs, typename Z>
+        static constexpr decltype(auto)
+        pick(Xs&&, Z&& z, hana::false_ /* odd index */)
+        { return static_cast<Z&&>(z); }
+
+        template <std::size_t i, typename Xs, typename Z>
+        static constexpr decltype(auto)
+        pick(Xs&& xs, Z&&, hana::true_ /* even index */)
+        { return hana::at_c<(i + 1) / 2>(static_cast<Xs&&>(xs)); }
+
+        template <typename Xs, typename Z, std::size_t ...i>
+        static constexpr auto
+        intersperse_helper(Xs&& xs, Z&& z, std::index_sequence<i...>) {
+            return hana::make<S>(
+                pick<i>(static_cast<Xs&&>(xs), static_cast<Z&&>(z),
+                        hana::bool_c<(i % 2 == 0)>)...
+            );
+        }
+
+        template <typename Xs, typename Z>
+        static constexpr auto apply(Xs&& xs, Z&& z) {
+            constexpr std::size_t size = decltype(hana::length(xs))::value;
+            constexpr std::size_t new_size = size == 0 ? 0 : (size * 2) - 1;
+            return intersperse_helper(static_cast<Xs&&>(xs), static_cast<Z&&>(z),
+                                      std::make_index_sequence<new_size>{});
+        }
+    };
+BOOST_HANA_NAMESPACE_END
+
+#endif // !BOOST_HANA_INTERSPERSE_HPP