Factor out commonalities between repeat and retry into a separate file (#363)

This reverts commit ad430c5bae364cf267f2b4a5cab703eb5672afbe.

* Retry operator: remove old comment

* Complete the error-reporting templates rollback

* Rename retry/repeat common file

* Fix filename in doxygen comment block

3 files changed, 195 insertions, 261 deletions

diff --git a/Rx/v2/src/rxcpp/operators/rx-repeat.hpp b/Rx/v2/src/rxcpp/operators/rx-repeat.hpp
index 3b11860..97ba197 100644
--- a/Rx/v2/src/rxcpp/operators/rx-repeat.hpp
+++ b/Rx/v2/src/rxcpp/operators/rx-repeat.hpp
@@ -25,6 +25,7 @@
 #define RXCPP_OPERATORS_RX_REPEAT_HPP
 
 #include "../rx-includes.hpp"
+#include "rx-retry-repeat-common.hpp"
 
 namespace rxcpp {
 
@@ -44,147 +45,36 @@ using repeat_invalid_t = typename repeat_invalid<AN...>::type;
 
 // Contain repeat variations in a namespace
 namespace repeat {
-  // Structure to perform general repeat operations on state
-  template <class ValuesType, class Subscriber, class T>
-  struct state_type : public std::enable_shared_from_this<state_type<ValuesType, Subscriber, T>>,
-                      public ValuesType {
-
-    typedef Subscriber output_type;
-    state_type(const ValuesType& i, const output_type& oarg)
-      : ValuesType(i),
-        source_lifetime(composite_subscription::empty()),
-        out(oarg) {
+  struct event_handlers {
+    template <typename State>
+    static inline void on_error(State& state, std::exception_ptr& e) {
+      state->out.on_error(e);
     }
           
-    void do_subscribe() {
-      auto state = this->shared_from_this();
-                
-      state->out.remove(state->lifetime_token);
-      state->source_lifetime.unsubscribe();
-
-      state->source_lifetime = composite_subscription();
-      state->lifetime_token = state->out.add(state->source_lifetime);
-
-      state->source.subscribe(
-                              state->out,
-                              state->source_lifetime,
-                              // on_next
-                              [state](T t) {
-                                state->out.on_next(t);
-                              },
-                              // on_error
-                              [state](std::exception_ptr e) {
-                                state->out.on_error(e);
-                              },
-                              // on_completed
-                              [state]() {
-                                state->update();
-                                // Use specialized predicate for finite/infinte case
-                                if (state->completed_predicate()) {
-                                  state->out.on_completed();
-                                } else {
-                                  state->do_subscribe();
-                                }
-                              }
-                              );
-    }
-          
-    composite_subscription source_lifetime;
-    output_type out;
-    composite_subscription::weak_subscription lifetime_token;
-  };
-
-  // Finite repeat case (explicitely limited with the number of times)
-  template <class T, class Observable, class Count>
-  struct finite : public operator_base<T> {
-    typedef rxu::decay_t<Observable> source_type;
-    typedef rxu::decay_t<Count> count_type;
-
-    struct values {
-      values(source_type s, count_type t)
-        : source(std::move(s)),
-          remaining_(std::move(t)) {
-      }
-
-      inline bool completed_predicate() const {
-        // Return true if we are completed
-        return remaining_ <= 0;
-      }
-      
-      inline void update() {
-        // Decrement counter
-        --remaining_;
-      }
-
-      source_type source;
-
-    private:
-      // Counter to hold number of times remaining to complete
-      count_type remaining_;
-    };
-    
-    finite(source_type s, count_type t)
-      : initial_(std::move(s), std::move(t)) {
-    }
-
-    template<class Subscriber>
-    void on_subscribe(const Subscriber& s) const {
-      typedef state_type<values, Subscriber, T> state_t;
-      // take a copy of the values for each subscription
-      auto state = std::make_shared<state_t>(initial_, s);      
-      if (initial_.completed_predicate()) {
-        // return completed
+    template <typename State>
+    static inline void on_completed(State& state) {
+      // Functions update() and completed_predicate() vary between finite and infinte versions
+      state->update();
+      if (state->completed_predicate()) {
         state->out.on_completed();
       } else {
-        // start the first iteration
         state->do_subscribe();
       }
     }
-
-  private:
-     values initial_;
   };
 
+  // Finite repeat case (explicitely limited with the number of times)
+  template <class T, class Observable, class Count>
+  using finite = ::rxcpp::operators::detail::retry_repeat_common::finite
+    <event_handlers, T, Observable, Count>;
+  
   // Infinite repeat case
   template <class T, class Observable>
-  struct infinite : public operator_base<T> {
-    typedef rxu::decay_t<Observable> source_type;
-    
-    struct values {
-      values(source_type s)
-        : source(std::move(s)) {
-      }
-
-      static inline bool completed_predicate() {
-        // Infinite repeat never completes
-        return false;
-      }
-
-      static inline void update() {
-        // Infinite repeat does not need to update state
-      }
-
-      source_type source;
-    };
-    
-    infinite(source_type s) : initial_(std::move(s)) {
-    }
-
-    template<class Subscriber>
-    void on_subscribe(const Subscriber& s) const {
-      typedef state_type<values, Subscriber, T> state_t;
-      // take a copy of the values for each subscription
-      auto state = std::make_shared<state_t>(initial_, s);
-      // start the first iteration
-      state->do_subscribe();
-    }
-
-  private:
-    values initial_;
-  };
-}
+  using infinite = ::rxcpp::operators::detail::retry_repeat_common::infinite
+    <event_handlers, T, Observable>;
 
 }
+} // detail
 
 /*! @copydoc rx-repeat.hpp
 */
diff --git a/Rx/v2/src/rxcpp/operators/rx-retry-repeat-common.hpp b/Rx/v2/src/rxcpp/operators/rx-retry-repeat-common.hpp
new file mode 100644
index 0000000..373d9b3
--- /dev/null
+++ b/Rx/v2/src/rxcpp/operators/rx-retry-repeat-common.hpp
@@ -0,0 +1,153 @@
+#pragma once
+
+/*! \file rx-retry-repeat-common.hpp
+
+    \brief Implementation commonalities between retry and repeat operators abstracted away from rx-retry.hpp and rx-repeat.hpp files. Should be used only from rx-retry.hpp and rx-repeat.hpp
+    
+*/
+
+#include "../rx-includes.hpp"
+
+namespace rxcpp {
+  namespace operators {
+    namespace detail {
+
+      namespace retry_repeat_common {
+        // Structure to perform general retry/repeat operations on state
+        template <class Values, class Subscriber, class EventHandlers, class T>
+        struct state_type : public std::enable_shared_from_this<state_type<Values, Subscriber, EventHandlers, T>>,
+                            public Values {
+
+          typedef Subscriber output_type;
+          state_type(const Values& i, const output_type& oarg)
+            : Values(i),
+              source_lifetime(composite_subscription::empty()),
+              out(oarg) {
+          }
+          
+          void do_subscribe() {
+            auto state = this->shared_from_this();
+                
+            state->out.remove(state->lifetime_token);
+            state->source_lifetime.unsubscribe();
+
+            state->source_lifetime = composite_subscription();
+            state->lifetime_token = state->out.add(state->source_lifetime);
+
+            state->source.subscribe(
+                                    state->out,
+                                    state->source_lifetime,
+                                    // on_next
+                                    [state](T t) {
+                                      state->out.on_next(t);
+                                    },
+                                    // on_error
+                                    [state](std::exception_ptr e) {
+                                      EventHandlers::on_error(state, e);
+                                    },
+                                    // on_completed
+                                    [state]() {
+                                      EventHandlers::on_completed(state);
+                                    }
+                                    );
+          }
+          
+          composite_subscription source_lifetime;
+          output_type out;
+          composite_subscription::weak_subscription lifetime_token;
+        };
+
+        // Finite case (explicitely limited with the number of times)
+        template <class EventHandlers, class T, class Observable, class Count>
+        struct finite : public operator_base<T> {
+          typedef rxu::decay_t<Observable> source_type;
+          typedef rxu::decay_t<Count> count_type;
+
+          struct values {
+            values(source_type s, count_type t)
+              : source(std::move(s)),
+                remaining_(std::move(t)) {
+            }
+
+            inline bool completed_predicate() const {
+              // Return true if we are completed
+              return remaining_ <= 0;
+            }
+      
+            inline void update() {
+              // Decrement counter
+              --remaining_;
+            }
+
+            source_type source;
+
+          private:
+            // Counter to hold number of times remaining to complete
+            count_type remaining_;
+          };
+    
+          finite(source_type s, count_type t)
+            : initial_(std::move(s), std::move(t)) {
+          }
+
+          template<class Subscriber>
+          void on_subscribe(const Subscriber& s) const {
+            typedef state_type<values, Subscriber, EventHandlers, T> state_t;
+            // take a copy of the values for each subscription
+            auto state = std::make_shared<state_t>(initial_, s);      
+            if (initial_.completed_predicate()) {
+              // return completed
+              state->out.on_completed();
+            } else {
+              // start the first iteration
+              state->do_subscribe();
+            }
+          }
+
+        private:
+          values initial_;
+        };
+
+        // Infinite case
+        template <class EventHandlers, class T, class Observable>
+        struct infinite : public operator_base<T> {
+          typedef rxu::decay_t<Observable> source_type;
+    
+          struct values {
+            values(source_type s)
+              : source(std::move(s)) {
+            }
+
+            static inline bool completed_predicate() {
+              // Infinite never completes
+              return false;
+            }
+
+            static inline void update() {
+              // Infinite does not need to update state
+            }
+
+            source_type source;
+          };
+    
+          infinite(source_type s) : initial_(std::move(s)) {
+          }
+
+          template<class Subscriber>
+          void on_subscribe(const Subscriber& s) const {
+            typedef state_type<values, Subscriber, EventHandlers, T> state_t;
+            // take a copy of the values for each subscription
+            auto state = std::make_shared<state_t>(initial_, s);
+            // start the first iteration
+            state->do_subscribe();
+          }
+
+        private:
+          values initial_;
+        };
+        
+        
+      }
+    }
+  }
+}
diff --git a/Rx/v2/src/rxcpp/operators/rx-retry.hpp b/Rx/v2/src/rxcpp/operators/rx-retry.hpp
index 073aa6c..3cee7d3 100644
--- a/Rx/v2/src/rxcpp/operators/rx-retry.hpp
+++ b/Rx/v2/src/rxcpp/operators/rx-retry.hpp
@@ -21,6 +21,7 @@
 #define RXCPP_OPERATORS_RX_RETRY_HPP
 
 #include "../rx-includes.hpp"
+#include "rx-retry-repeat-common.hpp"
 
 namespace rxcpp {
 
@@ -33,153 +34,43 @@ struct retry_invalid_arguments {};
 
 template<class... AN>
 struct retry_invalid : public rxo::operator_base<retry_invalid_arguments<AN...>> {
-    using type = observable<retry_invalid_arguments<AN...>, retry_invalid<AN...>>;
+  using type = observable<retry_invalid_arguments<AN...>, retry_invalid<AN...>>;
 };
 template<class... AN>
 using retry_invalid_t = typename retry_invalid<AN...>::type;
 
 // Contain retry variations in a namespace
 namespace retry {
-  // Structure to perform general retry operations on state
-  template <class ValuesType, class Subscriber, class T>
-  struct state_type : public std::enable_shared_from_this<state_type<ValuesType, Subscriber, T>>,
-                      public ValuesType {
-    typedef Subscriber output_type;
-    state_type(const ValuesType& i, const output_type& oarg)
-      : ValuesType(i)
-      , source_lifetime(composite_subscription::empty())
-      , out(oarg) {
-    }
-
-    void do_subscribe() {
-      auto state = this->shared_from_this();
-
-      state->out.remove(state->lifetime_token);
-      state->source_lifetime.unsubscribe();
-
-      state->source_lifetime = composite_subscription();
-      state->lifetime_token = state->out.add(state->source_lifetime);
-
-
-      state->source.subscribe(
-                              state->out,
-                              state->source_lifetime,
-                              // on_next
-                              [state](T t) {
-                                state->out.on_next(t);
-                              },
-                              // on_error
-                              [state](std::exception_ptr e) {
-                                state->update();
-                                // Use specialized predicate for finite/infinte case
-                                if (state->completed_predicate()) {
-                                  state->out.on_error(e);                                  
-                                } else {
-                                  state->do_subscribe();
-                                }
-                              },
-                              // on_completed
-                              [state]() {
-                                // JEP: never appeears to be called?
-                                state->out.on_completed();
-                              }
-                              );
-    }
-    
-    composite_subscription source_lifetime;
-    output_type out;
-    composite_subscription::weak_subscription lifetime_token;
-  };
-
-  // Finite retry case (explicitly limited with the number of times)
-  template<class T, class Observable, class Count>
-  struct finite : public operator_base<T> {
-    typedef rxu::decay_t<Observable> source_type;
-    typedef rxu::decay_t<Count> count_type;
-
-    struct values {
-      values(source_type s, count_type t)
-        : source(std::move(s)), remaining_(std::move(t)) {
-      }
-      
-      inline bool completed_predicate() const {
-        // Return true if we are completed
-        return remaining_ <= 0;
-      }
-      
-      inline void update() {
-        // Decrement counter
-        --remaining_;
-      }
-
-      source_type source;
-
-    private:
-      count_type remaining_;
-    };
-
-    finite(source_type s, count_type t)
-      : initial_(std::move(s), std::move(t)) {
-    }
-
-    template<class Subscriber>
-    void on_subscribe(const Subscriber& s) const {
-      typedef state_type<values, Subscriber, T> state_t;
-      // take a copy of the values for each subscription
-      auto state = std::make_shared<state_t>(initial_, s);
-      if (initial_.completed_predicate()) {
-        // Should we call it here in retry?
-        state->out.on_completed();
+  struct event_handlers {
+    template <typename State>
+    static inline void on_error(State& state, std::exception_ptr& e) {
+      state->update();
+      // Use specialized predicate for finite/infinte case
+      if (state->completed_predicate()) {
+        state->out.on_error(e);                                  
       } else {
-        // start the first iteration
         state->do_subscribe();
       }
     }
-
-  private:
-    values initial_;
-  };
-
-  // Infinite retry case
-  template<class T, class Observable>
-  struct infinite : public operator_base<T> {
-    typedef rxu::decay_t<Observable> source_type;
-
-    struct values {
-      values(source_type s)
-        : source(std::move(s)) {
-      }
-      
-      static inline bool completed_predicate() {
-        // Infinite retry never stops ignoring errors
-        return false;
-      }
-      
-      static inline void update() {
-        // Infinite retry does not need to update state
-      }
-
-      source_type source;
-    };
-
-    infinite(source_type s) : initial_(std::move(s)) {
-    }
-
-    template<class Subscriber>
-    void on_subscribe(const Subscriber& s) const {
-      typedef state_type<values, Subscriber, T> state_t;
-      // take a copy of the values for each subscription
-      auto state = std::make_shared<state_t>(initial_, s);
-      // start the first iteration
-      state->do_subscribe();
+          
+    template <typename State>
+    static inline void on_completed(State& state) {
+      state->out.on_completed();
     }
-
-  private:
-    values initial_;
   };
 
+  // Finite repeat case (explicitely limited with the number of times)
+  template <class T, class Observable, class Count>
+  using finite = ::rxcpp::operators::detail::retry_repeat_common::finite
+    <event_handlers, T, Observable, Count>;
+  
+  // Infinite repeat case
+  template <class T, class Observable>
+  using infinite = ::rxcpp::operators::detail::retry_repeat_common::infinite
+    <event_handlers, T, Observable>;
+  
 }
-}
+} // detail
 
 /*! @copydoc rx-retry.hpp
 */