277 lines
		
	
	
		
			10 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
		
		
			
		
	
	
			277 lines
		
	
	
		
			10 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
|   | // Copyright (c) Microsoft Open Technologies, Inc. All rights reserved. See License.txt in the project root for license information.
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|  | 
 | ||
|  | #pragma once
 | ||
|  | 
 | ||
|  | /*! \file rx-skip_until.hpp
 | ||
|  | 
 | ||
|  |     \brief Make new observable with items skipped until on_next occurs on the trigger observable or until the specified time. | ||
|  |            skip_until takes (TriggerObservable, optional Coordination) or (TimePoint, optional Coordination) | ||
|  | 
 | ||
|  |     \tparam  TriggerSource  the type of the trigger observable. | ||
|  |     \tparam  Coordination   the type of the scheduler (optional). | ||
|  | 
 | ||
|  |     \param  t  an observable that has to emit an item before the source observable's elements begin to be mirrored by the resulting observable. | ||
|  |     \param  cn  the scheduler to use for scheduling the items (optional). | ||
|  | 
 | ||
|  |     \return  An observable that skips items from the source observable until the second observable emits an item or the time runs out, then emits the remaining items. | ||
|  | 
 | ||
|  |     \sample | ||
|  |     \snippet skip_until.cpp skip_until sample | ||
|  |     \snippet output.txt skip_until sample | ||
|  | 
 | ||
|  |     \sample | ||
|  |     \snippet skip_until.cpp threaded skip_until sample | ||
|  |     \snippet output.txt threaded skip_until sample | ||
|  | */ | ||
|  | 
 | ||
|  | #if !defined(RXCPP_OPERATORS_RX_SKIP_UNTIL_HPP)
 | ||
|  | #define RXCPP_OPERATORS_RX_SKIP_UNTIL_HPP
 | ||
|  | 
 | ||
|  | #include "../rx-includes.hpp"
 | ||
|  | 
 | ||
|  | namespace rxcpp { | ||
|  | 
 | ||
|  | namespace operators { | ||
|  | 
 | ||
|  | namespace detail { | ||
|  | 
 | ||
|  | template<class... AN> | ||
|  | struct skip_until_invalid_arguments {}; | ||
|  | 
 | ||
|  | template<class... AN> | ||
|  | struct skip_until_invalid : public rxo::operator_base<skip_until_invalid_arguments<AN...>> { | ||
|  |     using type = observable<skip_until_invalid_arguments<AN...>, skip_until_invalid<AN...>>; | ||
|  | }; | ||
|  | template<class... AN> | ||
|  | using skip_until_invalid_t = typename skip_until_invalid<AN...>::type; | ||
|  | 
 | ||
|  | template<class T, class Observable, class TriggerObservable, class Coordination> | ||
|  | struct skip_until : public operator_base<T> | ||
|  | { | ||
|  |     typedef rxu::decay_t<Observable> source_type; | ||
|  |     typedef rxu::decay_t<TriggerObservable> trigger_source_type; | ||
|  |     typedef rxu::decay_t<Coordination> coordination_type; | ||
|  |     typedef typename coordination_type::coordinator_type coordinator_type; | ||
|  |     struct values | ||
|  |     { | ||
|  |         values(source_type s, trigger_source_type t, coordination_type sf) | ||
|  |             : source(std::move(s)) | ||
|  |             , trigger(std::move(t)) | ||
|  |             , coordination(std::move(sf)) | ||
|  |         { | ||
|  |         } | ||
|  |         source_type source; | ||
|  |         trigger_source_type trigger; | ||
|  |         coordination_type coordination; | ||
|  |     }; | ||
|  |     values initial; | ||
|  | 
 | ||
|  |     skip_until(source_type s, trigger_source_type t, coordination_type sf) | ||
|  |         : initial(std::move(s), std::move(t), std::move(sf)) | ||
|  |     { | ||
|  |     } | ||
|  | 
 | ||
|  |     struct mode | ||
|  |     { | ||
|  |         enum type { | ||
|  |             skipping,  // no messages from trigger
 | ||
|  |             clear,     // trigger completed
 | ||
|  |             triggered, // trigger sent on_next
 | ||
|  |             errored,   // error either on trigger or on observable
 | ||
|  |             stopped    // observable completed
 | ||
|  |         }; | ||
|  |     }; | ||
|  | 
 | ||
|  |     template<class Subscriber> | ||
|  |     void on_subscribe(Subscriber s) const { | ||
|  | 
 | ||
|  |         typedef Subscriber output_type; | ||
|  |         struct state_type | ||
|  |             : public std::enable_shared_from_this<state_type> | ||
|  |             , public values | ||
|  |         { | ||
|  |             state_type(const values& i, coordinator_type coor, const output_type& oarg) | ||
|  |                 : values(i) | ||
|  |                 , mode_value(mode::skipping) | ||
|  |                 , coordinator(std::move(coor)) | ||
|  |                 , out(oarg) | ||
|  |             { | ||
|  |                 out.add(trigger_lifetime); | ||
|  |                 out.add(source_lifetime); | ||
|  |             } | ||
|  |             typename mode::type mode_value; | ||
|  |             composite_subscription trigger_lifetime; | ||
|  |             composite_subscription source_lifetime; | ||
|  |             coordinator_type coordinator; | ||
|  |             output_type out; | ||
|  |         }; | ||
|  | 
 | ||
|  |         auto coordinator = initial.coordination.create_coordinator(); | ||
|  | 
 | ||
|  |         // take a copy of the values for each subscription
 | ||
|  |         auto state = std::make_shared<state_type>(initial, std::move(coordinator), std::move(s)); | ||
|  | 
 | ||
|  |         auto trigger = on_exception( | ||
|  |             [&](){return state->coordinator.in(state->trigger);}, | ||
|  |             state->out); | ||
|  |         if (trigger.empty()) { | ||
|  |             return; | ||
|  |         } | ||
|  | 
 | ||
|  |         auto source = on_exception( | ||
|  |             [&](){return state->coordinator.in(state->source);}, | ||
|  |             state->out); | ||
|  |         if (source.empty()) { | ||
|  |             return; | ||
|  |         } | ||
|  | 
 | ||
|  |         auto sinkTrigger = make_subscriber<typename trigger_source_type::value_type>( | ||
|  |         // share parts of subscription
 | ||
|  |             state->out, | ||
|  |         // new lifetime
 | ||
|  |             state->trigger_lifetime, | ||
|  |         // on_next
 | ||
|  |             [state](const typename trigger_source_type::value_type&) { | ||
|  |                 if (state->mode_value != mode::skipping) { | ||
|  |                     return; | ||
|  |                 } | ||
|  |                 state->mode_value = mode::triggered; | ||
|  |                 state->trigger_lifetime.unsubscribe(); | ||
|  |             }, | ||
|  |         // on_error
 | ||
|  |             [state](rxu::error_ptr e) { | ||
|  |                 if (state->mode_value != mode::skipping) { | ||
|  |                     return; | ||
|  |                 } | ||
|  |                 state->mode_value = mode::errored; | ||
|  |                 state->out.on_error(e); | ||
|  |             }, | ||
|  |         // on_completed
 | ||
|  |             [state]() { | ||
|  |                 if (state->mode_value != mode::skipping) { | ||
|  |                     return; | ||
|  |                 } | ||
|  |                 state->mode_value = mode::clear; | ||
|  |                 state->trigger_lifetime.unsubscribe(); | ||
|  |             } | ||
|  |         ); | ||
|  |         auto selectedSinkTrigger = on_exception( | ||
|  |             [&](){return state->coordinator.out(sinkTrigger);}, | ||
|  |             state->out); | ||
|  |         if (selectedSinkTrigger.empty()) { | ||
|  |             return; | ||
|  |         } | ||
|  |         trigger->subscribe(std::move(selectedSinkTrigger.get())); | ||
|  | 
 | ||
|  |         source.get().subscribe( | ||
|  |         // split subscription lifetime
 | ||
|  |             state->source_lifetime, | ||
|  |         // on_next
 | ||
|  |             [state](T t) { | ||
|  |                 if (state->mode_value != mode::triggered) { | ||
|  |                     return; | ||
|  |                 } | ||
|  |                 state->out.on_next(t); | ||
|  |             }, | ||
|  |         // on_error
 | ||
|  |             [state](rxu::error_ptr e) { | ||
|  |                 if (state->mode_value > mode::triggered) { | ||
|  |                     return; | ||
|  |                 } | ||
|  |                 state->mode_value = mode::errored; | ||
|  |                 state->out.on_error(e); | ||
|  |             }, | ||
|  |         // on_completed
 | ||
|  |             [state]() { | ||
|  |                 if (state->mode_value != mode::triggered) { | ||
|  |                     return; | ||
|  |                 } | ||
|  |                 state->mode_value = mode::stopped; | ||
|  |                 state->out.on_completed(); | ||
|  |             } | ||
|  |         ); | ||
|  |     } | ||
|  | }; | ||
|  | 
 | ||
|  | } | ||
|  | 
 | ||
|  | /*! @copydoc rx-skip_until.hpp
 | ||
|  | */ | ||
|  | template<class... AN> | ||
|  | auto skip_until(AN&&... an) | ||
|  |     ->     operator_factory<skip_until_tag, AN...> { | ||
|  |     return operator_factory<skip_until_tag, AN...>(std::make_tuple(std::forward<AN>(an)...)); | ||
|  | } | ||
|  | 
 | ||
|  | } | ||
|  | 
 | ||
|  | template<> | ||
|  | struct member_overload<skip_until_tag> | ||
|  | { | ||
|  |     template<class Observable, class TimePoint, | ||
|  |         class Enabled = rxu::enable_if_all_true_type_t< | ||
|  |             is_observable<Observable>, | ||
|  |             std::is_convertible<TimePoint, rxsc::scheduler::clock_type::time_point>>, | ||
|  |         class SourceValue = rxu::value_type_t<Observable>, | ||
|  |         class Timer = typename rxu::defer_type<rxs::detail::timer, identity_one_worker>::type, | ||
|  |         class TimerValue = rxu::value_type_t<Timer>, | ||
|  |         class TriggerObservable = observable<TimerValue, Timer>, | ||
|  |         class SkipUntil = rxo::detail::skip_until<SourceValue, rxu::decay_t<Observable>, TriggerObservable, identity_one_worker>, | ||
|  |         class Value = rxu::value_type_t<SkipUntil>, | ||
|  |         class Result = observable<Value, SkipUntil>> | ||
|  |     static Result member(Observable&& o, TimePoint&& when) { | ||
|  |         auto cn = identity_current_thread(); | ||
|  |         return Result(SkipUntil(std::forward<Observable>(o), rxs::timer(std::forward<TimePoint>(when), cn), cn)); | ||
|  |     } | ||
|  | 
 | ||
|  |     template<class Observable, class TimePoint, class Coordination, | ||
|  |         class Enabled = rxu::enable_if_all_true_type_t< | ||
|  |             is_observable<Observable>, | ||
|  |             is_coordination<Coordination>, | ||
|  |             std::is_convertible<TimePoint, rxsc::scheduler::clock_type::time_point>>, | ||
|  |         class SourceValue = rxu::value_type_t<Observable>, | ||
|  |         class Timer = typename rxu::defer_type<rxs::detail::timer, rxu::decay_t<Coordination>>::type, | ||
|  |         class TimerValue = rxu::value_type_t<Timer>, | ||
|  |         class TriggerObservable = observable<TimerValue, Timer>, | ||
|  |         class SkipUntil = rxo::detail::skip_until<SourceValue, rxu::decay_t<Observable>, TriggerObservable, rxu::decay_t<Coordination>>, | ||
|  |         class Value = rxu::value_type_t<SkipUntil>, | ||
|  |         class Result = observable<Value, SkipUntil>> | ||
|  |     static Result member(Observable&& o, TimePoint&& when, Coordination cn) { | ||
|  |         return Result(SkipUntil(std::forward<Observable>(o), rxs::timer(std::forward<TimePoint>(when), cn), cn)); | ||
|  |     } | ||
|  | 
 | ||
|  |     template<class Observable, class TriggerObservable, | ||
|  |         class Enabled = rxu::enable_if_all_true_type_t< | ||
|  |             all_observables<Observable, TriggerObservable>>, | ||
|  |         class SourceValue = rxu::value_type_t<Observable>, | ||
|  |         class SkipUntil = rxo::detail::skip_until<SourceValue, rxu::decay_t<Observable>, rxu::decay_t<TriggerObservable>, identity_one_worker>, | ||
|  |         class Value = rxu::value_type_t<SkipUntil>, | ||
|  |         class Result = observable<Value, SkipUntil>> | ||
|  |     static Result member(Observable&& o, TriggerObservable&& t) { | ||
|  |         return Result(SkipUntil(std::forward<Observable>(o), std::forward<TriggerObservable>(t), identity_current_thread())); | ||
|  |     } | ||
|  | 
 | ||
|  |      template<class Observable, class TriggerObservable, class Coordination, | ||
|  |         class Enabled = rxu::enable_if_all_true_type_t< | ||
|  |             all_observables<Observable, TriggerObservable>, | ||
|  |             is_coordination<Coordination>>, | ||
|  |         class SourceValue = rxu::value_type_t<Observable>, | ||
|  |         class SkipUntil = rxo::detail::skip_until<SourceValue, rxu::decay_t<Observable>, rxu::decay_t<TriggerObservable>, rxu::decay_t<Coordination>>, | ||
|  |         class Value = rxu::value_type_t<SkipUntil>, | ||
|  |         class Result = observable<Value, SkipUntil>> | ||
|  |     static Result member(Observable&& o, TriggerObservable&& t, Coordination&& cn) { | ||
|  |         return Result(SkipUntil(std::forward<Observable>(o), std::forward<TriggerObservable>(t), std::forward<Coordination>(cn))); | ||
|  |     } | ||
|  | 
 | ||
|  |     template<class... AN> | ||
|  |     static operators::detail::skip_until_invalid_t<AN...> member(AN...) { | ||
|  |         std::terminate(); | ||
|  |         return {}; | ||
|  |         static_assert(sizeof...(AN) == 10000, "skip_until takes (TriggerObservable, optional Coordination) or (TimePoint, optional Coordination)"); | ||
|  |     } | ||
|  | }; | ||
|  | 
 | ||
|  | } | ||
|  | 
 | ||
|  | #endif
 |