"J-P. Rosen" <rosen@adalog.fr> wrote in message 
news:pb6kuf$jgl$1@gioia.aioe.org...
> Le 17/04/2018 à 23:23, Dmitry A. Kazakov a écrit :
>> P.S. If "main subprogram complete" should mean "environment task
>> complete" that is OK to me. However insane the wording sounds to me only
>> the semantics counts.
> The paragraph you quote says "has completed", not "complete". Remember,
> the main subprogram is called by the environment task. So, the main
> subprogram completes and exits, then the environment task waits for
> dependents, at which point its 'callable becomes false.
>
>> Why could not "task complete" mean "will select
>> next terminate"? At least it would make some use out of having 
>> T'Callable.
> 'Callable is very useful for regular tasks. Your quote suggests that
> there might also be some use for it on the environment task, which is
> not obvious.

I invented that to get around Dmitry's original problem when I stumbled into 
it building Claw right after Ada 95 was finished. I was able to convince the 
ARG that the environment task ought to be completed once the main subprogram 
exits [that follows from the definition of the environment task], and that 
one should be able to use Ada.Task_Identification to query that. (You could 
do it even before the Environment_Task function, you just had to squirrel 
the environment task id during initial elaboration.) Several compilers 
didn't do this right, but one of the first things I added to the ACATS after 
taking over was a test of this case (once the ARG approved the idea, of 
course). So all modern compilers support the idiom of testing Callable of 
the environment task.

                       Randy.