I’m playing with tasks and have a question about select with delay until.

I have a task with the following body (the full implementation is on GitHub):

Wait : loop
   select
      -- Wait for pings. When they come, reset Last_Ping.
      accept Ping do
          Log.Debug ("Received ping.");
          Last_Ping := Clock;
      end Ping;
   or
      -- If there is no ping within the expected interval, do something.
      delay until (Last_Ping + Expected_Ping_Interval);
      Log.Error ("Timeout!");
      -- Do something.
      -- Is there any way to keep running the task loop here? 
   end select;
end loop Wait;

From how I understand the select, it waits for the specified delay - if there is a Ping before the end of the delay, the loop iteration is finished and the next iteration is started, again waiting for the specified delay or accepting a Ping.

Now, when the delay is over and there was no entry in Ping, it does not proceed with the next loop iteration but is finished, right? Why is that? And is there a way to write this loop so the task continues running?

(Also happily take pointers to good resources for learning about task behavior in more depth. )

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