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def handle_call(:get_history, _from, worker) do
  sortedLog = Enum.sort_by(worker.eventLog, fn event -> {event.time, event.origin} end)
  {:reply, sortedLog, worker}
end

deque-blog

def handle_info({:replication_log, logEntry}, worker) do
  newWorkerState =
    if logEntry.origin == worker.name do
      worker
    else
      %{ worker |
        clock: max(worker.clock, logEntry.time) + 1,
        eventLog: [logEntry | worker.eventLog] }
    end
  {:noreply, newWorkerState }

deque-blog

def handle_call({:add, event}, _from, worker) do
  logEntry = %LogEntry{
    origin: worker.name,
    time: worker.clock,
    event: event
  }
  newWorkerState = %{ worker |
    clock: worker.clock + 1,
    eventLog: [logEntry | worker.eventLog]
  }

deque-blog

private void pollSweeperTable(Session session) {
    List<Message> unsentMessages = messageRepository.fetchUnsentMessages();
    for (Message message : unsentMessages)
        sendMessage(session, message);
    messageRepository.markSent(unsentMessages); // One DB transaction
}

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@Modifying
@Query(
   value = "update SweeperTable set sent = 1 where messageId in (:messageIds)",
   nativeQuery = true)
void markSent(@Param("messageIds") List<Long> messageIds);

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try {
   pollSweeperTable(Session session);
   // ...
} catch (Exception e) {
   // Log the exception
}

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private void pollSweeperTable(Session session) {
    List<Message> unsentMessages = messageRepository.fetchUnsentMessages();
    for (Message message : unsentMessages)
        sendMessage(session, message);
    messageRepository.markSent(unsentMessages);
}

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testCombination = do         -- a new computation in our DSL in which we:
  p1 <- suggestedPostsFor 1  -- * compute the suggested posts for user 1
  p1' <- suggestedPostsFor 1 -- * compute the suggested posts for user 1 (again)
  p2 <- suggestedPostsFor 2  -- * compute the suggested posts for user 2
  return (p1, p1', p2)       -- * return a tuple with the result of these computations

deque-blog

template<typename Iterator>
struct IteratorTraits {};

template<>
struct IteratorTraits<LinkedListIterator>
{
   using iterator_category = std::bidirectional_iterator_tag;
};

template<>

deque-blog

AdditionalTag<RandomAccessIterator<Iterator>>
RandomAccessIterator<AdditionalTag<Iterator>>