Re: Exception Propagation

[Robert Dewar <robert_dewar@my-deja.com>]

In article <0nc73.5376$y6.3195132@WReNphoon3>,
  cdecker@snet.net (Decker, Christian R) wrote:
> OK, everyone is mis-understanding my question, and i
apologize.....
> I understand that when an exception is raised in a task that
it is not
> deterministic as to where the exception gets
> propagated as far as being able to trap and handle it.

No, that's confused, the exception is NOT propagated at all!

> But as far as seeing text displayed in the console window
> indicating that an
> excpetion was raised should always
> occur, at least in every other Ada compiler i have used.

Not unconditionally certainly. Terminating a task with an
unhandled exception is not an error, it is perfectly well
behaved Ada semantics. You cannot justify a compiler outputting
junk in some console window just because it thinks you are using
a feature of Ada which you should not be!

>  My problem is that
> i see no text, or any other indication
> that an exception is being raised.  I know there is an
> exception because i
> tested using an explicit trap to display
> the error.  I don't want random exception handles, i just want
> to be
> notified via text in the console that an
> exception has occured.

Then put a when others handler in your task at the outer level,
dumping the exception information. Your compiler *may* have a
special non-standard non-RM mode in which it treats this
situation as an error, or dumps stuff to some window, but there
is no requirement (or even suggestion) in the RM that such
behavior is desirable, let alone required.

> So with that does anyone know why i am not getting text
> messages telling me an exception was raised?

Because the exception was not unhandled, there is no such
thing as an unhandled exception in a task, instead if no
handler is found, the semantics is that the exception is
silently handled, and the task terminates.


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