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 +1,110 @@
+/*!
+@file
+Defines `boost::hana::overload_linearly`.
+
+@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_FUNCTIONAL_OVERLOAD_LINEARLY_HPP
+#define BOOST_HANA_FUNCTIONAL_OVERLOAD_LINEARLY_HPP
+
+#include <boost/hana/config.hpp>
+#include <boost/hana/detail/decay.hpp>
+
+#include <utility>
+
+
+BOOST_HANA_NAMESPACE_BEGIN
+    //! @ingroup group-functional
+    //! Call the first function that produces a valid call expression.
+    //!
+    //! Given functions `f1, ..., fn`, `overload_linearly(f1, ..., fn)` is
+    //! a new function that calls the first `fk` producing a valid call
+    //! expression with the given arguments. Specifically,
+    //! @code
+    //!     overload_linearly(f1, ..., fn)(args...) == fk(args...)
+    //! @endcode
+    //!
+    //! where `fk` is the _first_ function such that `fk(args...)` is a valid
+    //! expression.
+    //!
+    //!
+    //! Example
+    //! -------
+    //! @include example/functional/overload_linearly.cpp
+#ifdef BOOST_HANA_DOXYGEN_INVOKED
+    constexpr auto overload_linearly = [](auto&& f1, auto&& f2, ..., auto&& fn) {
+        return [perfect-capture](auto&& ...x) -> decltype(auto) {
+            return forwarded(fk)(forwarded(x)...);
+        };
+    };
+#else
+    template <typename F, typename G>
+    struct overload_linearly_t {
+        F f;
+        G g;
+
+    private:
+        template <typename ...Args, typename =
+            decltype(std::declval<F const&>()(std::declval<Args>()...))>
+        constexpr F const& which(int) const& { return f; }
+
+        template <typename ...Args, typename =
+            decltype(std::declval<F&>()(std::declval<Args>()...))>
+        constexpr F& which(int) & { return f; }
+
+        template <typename ...Args, typename =
+            decltype(std::declval<F&&>()(std::declval<Args>()...))>
+        constexpr F which(int) && { return static_cast<F&&>(f); }
+
+        template <typename ...Args>
+        constexpr G const& which(long) const& { return g; }
+
+        template <typename ...Args>
+        constexpr G& which(long) & { return g; }
+
+        template <typename ...Args>
+        constexpr G which(long) && { return static_cast<G&&>(g); }
+
+    public:
+        template <typename ...Args>
+        constexpr decltype(auto) operator()(Args&& ...args) const&
+        { return which<Args...>(int{})(static_cast<Args&&>(args)...); }
+
+        template <typename ...Args>
+        constexpr decltype(auto) operator()(Args&& ...args) &
+        { return which<Args...>(int{})(static_cast<Args&&>(args)...); }
+
+        template <typename ...Args>
+        constexpr decltype(auto) operator()(Args&& ...args) &&
+        { return which<Args...>(int{})(static_cast<Args&&>(args)...); }
+    };
+
+    struct make_overload_linearly_t {
+        template <typename F, typename G>
+        constexpr overload_linearly_t<
+            typename detail::decay<F>::type,
+            typename detail::decay<G>::type
+        > operator()(F&& f, G&& g) const {
+            return {static_cast<F&&>(f), static_cast<G&&>(g)};
+        }
+
+        template <typename F, typename G, typename ...H>
+        constexpr decltype(auto) operator()(F&& f, G&& g, H&& ...h) const {
+            return (*this)(static_cast<F&&>(f),
+                    (*this)(static_cast<G&&>(g), static_cast<H&&>(h)...));
+        }
+
+        template <typename F>
+        constexpr typename detail::decay<F>::type operator()(F&& f) const {
+            return static_cast<F&&>(f);
+        }
+    };
+
+    constexpr make_overload_linearly_t overload_linearly{};
+#endif
+BOOST_HANA_NAMESPACE_END
+
+#endif // !BOOST_HANA_FUNCTIONAL_OVERLOAD_LINEARLY_HPP