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From: Robert A Duff <bobduff@shell01.TheWorld.com>
Newsgroups: comp.lang.ada
Subject: Re: Is Text_IO.Put_Line() thread-safe?
Date: Thu, 14 Jun 2012 14:34:46 -0400
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Date: 2012-06-14T14:34:46-04:00
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"J-P. Rosen" <rosen@adalog.fr> writes:

> Asynchronous raising of exceptions was in preliminary Ada, the issue was
> studied, and removed for Ada 83.

Not really.  It was renamed to be "abort".  The semantics of
"abort" in Ada 83 are essentially the same as the semantics
of T'Failure in preliminary Ada.

In all Ada implementations I have worked on (which is a lot),
abort is implemented internally via a special exception that
is invisible to user code.

In any case, it doesn't make sense for a single task to be
raising two exceptions at the same time, so that must be
prevented.  Likewise simultaneously aborting and raising
an exception.

- Bob