feat add rxcpp

3party/rxcpp/operators/rx-on_error_resume_next.hpp

@@ -0,0 +1,147 @@
+// Copyright (c) Microsoft Open Technologies, Inc. All rights reserved. See License.txt in the project root for license information.
+
+#pragma once
+
+/*! \file rx-on_error_resume_next.hpp
+
+    \brief If an error occurs, take the result from the Selector and subscribe to that instead.
+
+    \tparam Selector the actual type of a function of the form `observable<T>(rxu::error_ptr)`
+
+    \param s the function of the form `observable<T>(rxu::error_ptr)`
+
+    \return Observable that emits the items from the source observable and switches to a new observable on error.
+
+    \sample
+    \snippet on_error_resume_next.cpp on_error_resume_next sample
+    \snippet output.txt on_error_resume_next sample
+*/
+
+#if !defined(RXCPP_OPERATORS_RX_ON_ERROR_RESUME_NEXT_HPP)
+#define RXCPP_OPERATORS_RX_ON_ERROR_RESUME_NEXT_HPP
+
+#include "../rx-includes.hpp"
+
+namespace rxcpp {
+
+namespace operators {
+
+namespace detail {
+
+template<class... AN>
+struct on_error_resume_next_invalid_arguments {};
+
+template<class... AN>
+struct on_error_resume_next_invalid : public rxo::operator_base<on_error_resume_next_invalid_arguments<AN...>> {
+    using type = observable<on_error_resume_next_invalid_arguments<AN...>, on_error_resume_next_invalid<AN...>>;
+};
+template<class... AN>
+using on_error_resume_next_invalid_t = typename on_error_resume_next_invalid<AN...>::type;
+
+
+template<class T, class Selector>
+struct on_error_resume_next
+{
+    typedef rxu::decay_t<T> value_type;
+    typedef rxu::decay_t<Selector> select_type;
+    typedef decltype((*(select_type*)nullptr)(rxu::error_ptr())) fallback_type;
+    select_type selector;
+
+    on_error_resume_next(select_type s)
+        : selector(std::move(s))
+    {
+    }
+
+    template<class Subscriber>
+    struct on_error_resume_next_observer
+    {
+        typedef on_error_resume_next_observer<Subscriber> this_type;
+        typedef rxu::decay_t<T> value_type;
+        typedef rxu::decay_t<Selector> select_type;
+        typedef decltype((*(select_type*)nullptr)(rxu::error_ptr())) fallback_type;
+        typedef rxu::decay_t<Subscriber> dest_type;
+        typedef observer<T, this_type> observer_type;
+        dest_type dest;
+        composite_subscription lifetime;
+        select_type selector;
+
+        on_error_resume_next_observer(dest_type d, composite_subscription cs, select_type s)
+            : dest(std::move(d))
+            , lifetime(std::move(cs))
+            , selector(std::move(s))
+        {
+            dest.add(lifetime);
+        }
+        void on_next(value_type v) const {
+            dest.on_next(std::move(v));
+        }
+        void on_error(rxu::error_ptr e) const {
+            auto selected = on_exception(
+                [&](){
+                    return this->selector(std::move(e));},
+                dest);
+            if (selected.empty()) {
+                return;
+            }
+            selected->subscribe(dest);
+        }
+        void on_completed() const {
+            dest.on_completed();
+        }
+
+        static subscriber<T, observer_type> make(dest_type d, select_type s) {
+            auto cs = composite_subscription();
+            return make_subscriber<T>(cs, observer_type(this_type(std::move(d), cs, std::move(s))));
+        }
+    };
+
+    template<class Subscriber>
+    auto operator()(Subscriber dest) const
+        -> decltype(on_error_resume_next_observer<Subscriber>::make(std::move(dest), selector)) {
+        return      on_error_resume_next_observer<Subscriber>::make(std::move(dest), selector);
+    }
+};
+
+}
+
+/*! @copydoc rx-on_error_resume_next.hpp
+*/
+template<class... AN>
+auto on_error_resume_next(AN&&... an)
+    ->     operator_factory<on_error_resume_next_tag, AN...> {
+    return operator_factory<on_error_resume_next_tag, AN...>(std::make_tuple(std::forward<AN>(an)...));
+}
+
+/*! @copydoc rx-on_error_resume_next.hpp
+*/
+template<class... AN>
+auto switch_on_error(AN&&... an)
+    ->     operator_factory<on_error_resume_next_tag, AN...> {
+    return operator_factory<on_error_resume_next_tag, AN...>(std::make_tuple(std::forward<AN>(an)...));
+}
+
+}
+
+template<>
+struct member_overload<on_error_resume_next_tag>
+{
+    template<class Observable, class Selector,
+            class SourceValue = rxu::value_type_t<Observable>,
+            class OnErrorResumeNext = rxo::detail::on_error_resume_next<SourceValue, rxu::decay_t<Selector>>,
+            class Value = rxu::value_type_t<OnErrorResumeNext>>
+    static auto member(Observable&& o, Selector&& p)
+    -> decltype(o.template lift<Value>(OnErrorResumeNext(std::forward<Selector>(p)))) {
+        return      o.template lift<Value>(OnErrorResumeNext(std::forward<Selector>(p)));
+    }
+
+    template<class... AN>
+    static operators::detail::on_error_resume_next_invalid_t<AN...> member(const AN&...) {
+        std::terminate();
+        return {};
+        static_assert(sizeof...(AN) == 10000, "on_error_resume_next takes (Selector)");
+    }
+};
+
+}
+
+#endif