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

depends/x86_64-pc-linux-gnu/include/boost/hana/detail/index_if.hpp

@@ -0,0 +1,71 @@
+/*!
+@file
+Defines `boost::hana::detail::index_if`.
+
+@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_DETAIL_INDEX_IF_HPP
+#define BOOST_HANA_DETAIL_INDEX_IF_HPP
+
+#include <boost/hana/config.hpp>
+#include <boost/hana/core/when.hpp>
+
+#include <cstddef>
+#include <utility>
+
+
+BOOST_HANA_NAMESPACE_BEGIN namespace detail {
+    template <typename ...T>
+    struct pack {
+        static constexpr std::size_t length = sizeof...(T);
+    };
+
+    template <typename T>
+    struct make_pack;
+
+    template <template <typename...> class Template, typename ...T>
+    struct make_pack<Template<T...>> {
+        using type = pack<T...>;
+    };
+
+    template <typename T> struct make_pack<T const> : make_pack<T> { };
+    template <typename T> struct make_pack<T&> : make_pack<T> { };
+    template <typename T> struct make_pack<T&&> : make_pack<T> { };
+
+
+    //! @ingroup group-details
+    //! Returns the index of the first element of the `pack<>` that satisfies
+    //! the predicate, or the size of the pack if there is no such element.
+    //!
+    //! @note
+    //! The predicate must return an `IntegralConstant` that can be explicitly
+    //! converted to `bool`.
+    template <typename Pred, typename Ts, typename = when<true>>
+    struct index_if;
+
+    //! @cond
+    template <typename Pred, typename T, typename ...Ts>
+    struct index_if<Pred, pack<T, Ts...>, when<static_cast<bool>(decltype(
+        std::declval<Pred>()(std::declval<T>())
+    )::value)>> {
+        static constexpr std::size_t value = 0;
+    };
+
+    template <typename Pred, typename T, typename ...Ts>
+    struct index_if<Pred, pack<T, Ts...>, when<!static_cast<bool>(decltype(
+        std::declval<Pred>()(std::declval<T>())
+    )::value)>> {
+        static constexpr std::size_t value = 1 + index_if<Pred, pack<Ts...>>::value;
+    };
+
+    template <typename Pred>
+    struct index_if<Pred, pack<>> {
+        static constexpr std::size_t value = 0;
+    };
+    //! @endcond
+} BOOST_HANA_NAMESPACE_END
+
+#endif // !BOOST_HANA_DETAIL_INDEX_IF_HPP