git.sesse.net Git - casparcg/blob - dependencies64/RxCpp/include/rxcpp/operators/rx-map.hpp

   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 #if !defined(RXCPP_OPERATORS_RX_MAP_HPP)
   6 #define RXCPP_OPERATORS_RX_MAP_HPP
   7
   8 #include "../rx-includes.hpp"
   9
  10 namespace rxcpp {
  11
  12 namespace operators {
  13
  14 namespace detail {
  15
  16
  17 template<class T, class Selector>
  18 struct map
  19 {
  20     typedef typename std::decay<T>::type source_value_type;
  21     typedef typename std::decay<Selector>::type select_type;
  22     typedef decltype((*(select_type*)nullptr)(*(source_value_type*)nullptr)) value_type;
  23     select_type selector;
  24
  25     map(select_type s)
  26         : selector(std::move(s))
  27     {
  28     }
  29
  30     template<class Subscriber>
  31     struct map_observer
  32     {
  33         typedef map_observer<Subscriber> this_type;
  34         typedef decltype((*(select_type*)nullptr)(*(source_value_type*)nullptr)) value_type;
  35         typedef typename std::decay<Subscriber>::type dest_type;
  36         typedef observer<T, this_type> observer_type;
  37         dest_type dest;
  38         select_type selector;
  39
  40         map_observer(dest_type d, select_type s)
  41             : dest(std::move(d))
  42             , selector(std::move(s))
  43         {
  44         }
  45         void on_next(source_value_type v) const {
  46             auto selected = on_exception(
  47                 [&](){
  48                     return this->selector(std::move(v));},
  49                 dest);
  50             if (selected.empty()) {
  51                 return;
  52             }
  53             dest.on_next(std::move(selected.get()));
  54         }
  55         void on_error(std::exception_ptr e) const {
  56             dest.on_error(e);
  57         }
  58         void on_completed() const {
  59             dest.on_completed();
  60         }
  61
  62         static subscriber<T, observer_type> make(dest_type d, select_type s) {
  63             auto cs = d.get_subscription();
  64             return make_subscriber<T>(std::move(cs), observer_type(this_type(std::move(d), std::move(s))));
  65         }
  66     };
  67
  68     template<class Subscriber>
  69     auto operator()(Subscriber dest) const
  70         -> decltype(map_observer<Subscriber>::make(std::move(dest), selector)) {
  71         return      map_observer<Subscriber>::make(std::move(dest), selector);
  72     }
  73 };
  74
  75 template<class Selector>
  76 class map_factory
  77 {
  78     typedef typename std::decay<Selector>::type select_type;
  79     select_type selector;
  80 public:
  81     map_factory(select_type s) : selector(std::move(s)) {}
  82     template<class Observable>
  83     auto operator()(Observable&& source)
  84         -> decltype(source.template lift<typename map<typename std::decay<Observable>::type::value_type, select_type>::value_type>(map<typename std::decay<Observable>::type::value_type, select_type>(selector))) {
  85         return      source.template lift<typename map<typename std::decay<Observable>::type::value_type, select_type>::value_type>(map<typename std::decay<Observable>::type::value_type, select_type>(selector));
  86     }
  87 };
  88
  89 }
  90
  91 template<class Selector>
  92 auto map(Selector&& p)
  93     ->      detail::map_factory<Selector> {
  94     return  detail::map_factory<Selector>(std::forward<Selector>(p));
  95 }
  96
  97 }
  98
  99 }
 100
 101 #endif