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Date: Sun, 4 Mar 2018 10:22:56 -0800 (PST)
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Subject: multiple delay alternative
From: Mehdi Saada <00120260a@gmail.com>
Injection-Date: Sun, 04 Mar 2018 18:22:56 +0000
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Xref: reader02.eternal-september.org comp.lang.ada:50817
Date: 2018-03-04T10:22:56-08:00
List-Id: <comp.lang.ada>

Hello !

In https://perso.telecom-paristech.fr/pautet/Ada95/chap28.htm, Ada tutorial's paragraph on the delayed rendezvous, it says the general form of this construct is:
select 
         delay <time>;
         <entry call>;
    or 
         delay <time>;
         <entry call>;
    or
         delay <time>;
         <entry call>;
    end select;

But in the RM timed entry calls are featured like this:
timed_entry_call ::= 
  select
   entry_call_alternative
  or
   delay_alternative
  end select;

What should I understand ?
I have trouble understanding the first construct, otherwise than "if nothing happens before n seconds, do that, AND THEN, if nothing happens before n2 seconds, do that, etc... as if
select
     delay 11.0;
     A;
or
     delay 12.0
     B;
end select;

is equivalent to
delay 10.0
select
     delay 1.0;
or
     delay 2.0;
end select;
But it's likely that I didn't guess right.