1 // Copyright (c) Microsoft Open Technologies, Inc. All rights reserved. See License.txt in the project root for license information.
2
3 #pragma once
4
5 /*! \file rx-repeat.hpp
6
7 \brief Repeat this observable for the given number of times or infinitely.
8
9 \tparam Count the type of the counter (optional).
10
11 \param t The number of times the source observable items are repeated (optional). If not specified, infinitely repeats the source observable. Specifying 0 returns an empty sequence immediately
12
13 \return An observable that repeats the sequence of items emitted by the source observable for t times.
14
15 \sample
16 \snippet repeat.cpp repeat count sample
17 \snippet output.txt repeat count sample
18
19 If the source observable calls on_error, repeat stops:
20 \snippet repeat.cpp repeat error sample
21 \snippet output.txt repeat error sample
22 */
23
24 #if !defined(RXCPP_OPERATORS_RX_REPEAT_HPP)
25 #define RXCPP_OPERATORS_RX_REPEAT_HPP
26
27 #include "../rx-includes.hpp"
28 #include "rx-retry-repeat-common.hpp"
29
30 namespace rxcpp {
31
32 namespace operators {
33
34 namespace detail {
35
36 template<class... AN>
37 struct repeat_invalid_arguments {};
38
39 template<class... AN>
40 struct repeat_invalid : public rxo::operator_base<repeat_invalid_arguments<AN...>> {
41 using type = observable<repeat_invalid_arguments<AN...>, repeat_invalid<AN...>>;
42 };
43 template<class... AN>
44 using repeat_invalid_t = typename repeat_invalid<AN...>::type;
45
46 // Contain repeat variations in a namespace
47 namespace repeat {
48 struct event_handlers {
49 template <typename State>
on_errorrxcpp::operators::detail::repeat::event_handlers50 static inline void on_error(State& state, rxu::error_ptr& e) {
51 state->out.on_error(e);
52 }
53
54 template <typename State>
on_completedrxcpp::operators::detail::repeat::event_handlers55 static inline void on_completed(State& state) {
56 // Functions update() and completed_predicate() vary between finite and infinte versions
57 state->update();
58 if (state->completed_predicate()) {
59 state->out.on_completed();
60 } else {
61 state->do_subscribe();
62 }
63 }
64 };
65
66 // Finite repeat case (explicitely limited with the number of times)
67 template <class T, class Observable, class Count>
68 using finite = ::rxcpp::operators::detail::retry_repeat_common::finite
69 <event_handlers, T, Observable, Count>;
70
71 // Infinite repeat case
72 template <class T, class Observable>
73 using infinite = ::rxcpp::operators::detail::retry_repeat_common::infinite
74 <event_handlers, T, Observable>;
75
76 }
77 } // detail
78
79 /*! @copydoc rx-repeat.hpp
80 */
81 template<class... AN>
repeat(AN &&...an)82 auto repeat(AN&&... an)
83 -> operator_factory<repeat_tag, AN...> {
84 return operator_factory<repeat_tag, AN...>(std::make_tuple(std::forward<AN>(an)...));
85 }
86
87 }
88
89 template<>
90 struct member_overload<repeat_tag> {
91 template<class Observable,
92 class Enabled = rxu::enable_if_all_true_type_t<is_observable<Observable>>,
93 class SourceValue = rxu::value_type_t<Observable>,
94 class Repeat = rxo::detail::repeat::infinite<SourceValue, rxu::decay_t<Observable>>,
95 class Value = rxu::value_type_t<Repeat>,
96 class Result = observable<Value, Repeat>>
memberrxcpp::member_overload97 static Result member(Observable&& o) {
98 return Result(Repeat(std::forward<Observable>(o)));
99 }
100
101 template<class Observable,
102 class Count,
103 class Enabled = rxu::enable_if_all_true_type_t<is_observable<Observable>>,
104 class SourceValue = rxu::value_type_t<Observable>,
105 class Repeat = rxo::detail::repeat::finite<SourceValue, rxu::decay_t<Observable>, rxu::decay_t<Count>>,
106 class Value = rxu::value_type_t<Repeat>,
107 class Result = observable<Value, Repeat>>
memberrxcpp::member_overload108 static Result member(Observable&& o, Count&& c) {
109 return Result(Repeat(std::forward<Observable>(o), std::forward<Count>(c)));
110 }
111
112 template<class... AN>
memberrxcpp::member_overload113 static operators::detail::repeat_invalid_t<AN...> member(AN...) {
114 std::terminate();
115 return {};
116 static_assert(sizeof...(AN) == 10000, "repeat takes (optional Count)");
117 }
118 };
119
120 }
121
122 #endif
123