feat add rxcpp

3party/rxcpp/sources/rx-create.hpp

@@ -0,0 +1,92 @@
+// Copyright (c) Microsoft Open Technologies, Inc. All rights reserved. See License.txt in the project root for license information.
+
+#pragma once
+
+#if !defined(RXCPP_SOURCES_RX_CREATE_HPP)
+#define RXCPP_SOURCES_RX_CREATE_HPP
+
+#include "../rx-includes.hpp"
+
+/*! \file rx-create.hpp
+
+    \brief Returns an observable that executes the specified function when a subscriber subscribes to it.
+
+    \tparam T  the type of the items that this observable emits
+    \tparam OnSubscribe  the type of OnSubscribe handler function
+
+    \param  os  OnSubscribe event handler
+
+    \return  Observable that executes the specified function when a Subscriber subscribes to it.
+
+    \sample
+    \snippet create.cpp Create sample
+    \snippet output.txt Create sample
+
+    \warning
+    It is good practice to check the observer's is_subscribed state from within the function you pass to create
+    so that your observable can stop emitting items or doing expensive calculations when there is no longer an interested observer.
+
+    \badcode
+    \snippet create.cpp Create bad code
+    \snippet output.txt Create bad code
+
+    \goodcode
+    \snippet create.cpp Create good code
+    \snippet output.txt Create good code
+
+    \warning
+    It is good practice to use operators like observable::take to control lifetime rather than use the subscription explicitly.
+
+    \goodcode
+    \snippet create.cpp Create great code
+    \snippet output.txt Create great code
+*/
+
+namespace rxcpp {
+
+namespace sources {
+
+namespace detail {
+
+template<class T, class OnSubscribe>
+struct create : public source_base<T>
+{
+    typedef create<T, OnSubscribe> this_type;
+
+    typedef rxu::decay_t<OnSubscribe> on_subscribe_type;
+
+    on_subscribe_type on_subscribe_function;
+
+    create(on_subscribe_type os)
+        : on_subscribe_function(std::move(os))
+    {
+    }
+
+    template<class Subscriber>
+    void on_subscribe(Subscriber o) const {
+
+        on_exception(
+            [&](){
+                this->on_subscribe_function(o);
+                return true;
+            },
+            o);
+    }
+};
+
+}
+
+/*! @copydoc rx-create.hpp
+    */
+template<class T, class OnSubscribe>
+auto create(OnSubscribe os)
+    ->      observable<T,   detail::create<T, OnSubscribe>> {
+    return  observable<T,   detail::create<T, OnSubscribe>>(
+                            detail::create<T, OnSubscribe>(std::move(os)));
+}
+
+}
+
+}
+
+#endif