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diff --git a/learn-you-some-erlang/reminder/src/dev_event.erl b/learn-you-some-erlang/reminder/src/dev_event.erl
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+%%% This module is there to test the incomplete loops and constructs
+%%% that are presented in the text, but are not the final result.
+-module(dev_event).
+-compile(export_all).
+-record(state, {server,
+ name="",
+ to_go=0}).
+
+start1(EventName, Delay) ->
+ spawn(?MODULE, init1, [self(), EventName, Delay]).
+
+start_link1(EventName, Delay) ->
+ spawn_link(?MODULE, init1, [self(), EventName, Delay]).
+
+start2(EventName, Delay) ->
+ spawn(?MODULE, init2, [self(), EventName, Delay]).
+
+start_link2(EventName, Delay) ->
+ spawn_link(?MODULE, init2, [self(), EventName, Delay]).
+
+cancel(Pid) ->
+ %% Monitor in case the process is already dead
+ Ref = erlang:monitor(process, Pid),
+ Pid ! {self(), Ref, cancel},
+ receive
+ {Ref, ok} ->
+ erlang:demonitor(Ref, [flush]),
+ ok;
+ {'DOWN', Ref, process, Pid, _Reason} ->
+ ok
+ end.
+
+
+
+%%% Event's innards
+init1(Server, EventName, Delay) ->
+ loop2(#state{server=Server,
+ name=EventName,
+ to_go=normalize(Delay)}).
+
+init2(Server, EventName, DateTime) ->
+ loop2(#state{server=Server,
+ name=EventName,
+ to_go=time_to_go(DateTime)}).
+
+loop1(S = #state{server=Server}) ->
+ receive
+ {Server, Ref, cancel} ->
+ Server ! {Ref, ok}
+ after S#state.to_go * 1000 ->
+ Server ! {done, S#state.name}
+ end.
+
+%% Loop uses a list for times in order to go around the ~49 days limit
+%% on timeouts.
+loop2(S = #state{server=Server, to_go=[T|Next]}) ->
+ receive
+ {Server, Ref, cancel} ->
+ Server ! {Ref, ok}
+ after T*1000 ->
+ if Next =:= [] ->
+ Server ! {done, S#state.name};
+ Next =/= [] ->
+ loop2(S#state{to_go=Next})
+ end
+ end.
+
+
+time_to_go(TimeOut={{_,_,_}, {_,_,_}}) ->
+ Now = calendar:local_time(),
+ ToGo = calendar:datetime_to_gregorian_seconds(TimeOut) -
+ calendar:datetime_to_gregorian_seconds(Now),
+ Secs = if ToGo > 0 -> ToGo;
+ ToGo =< 0 -> 0
+ end,
+ normalize(Secs).
+
+%% Because Erlang is limited to about 49 days (49*24*60*60*1000) in
+%% milliseconds, the following function is used
+normalize(N) ->
+ Limit = 49*24*60*60,
+ [N rem Limit | lists:duplicate(N div Limit, Limit)].