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From: "Sergey Koshcheyev" <serko84@hotmail.com>
Newsgroups: comp.lang.ada
Subject: Re: I/O - exception handling
Date: Mon, 26 May 2003 16:39:54 +0200
Organization: Czech Technical University
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"Preben Randhol" <randhol+abuse@pvv.org> wrote in message
news:slrnbd494u.523.randhol+abuse@kiuk0152.chembio.ntnu.no...
> Sergey Koshcheyev wrote:
> I do this check in my application so the user can get propper feedback:
>
>       exception
>          when Name_Error =>

<snip>

>       end;

OK, I'll try to explain my problem on your example. You report the error.
Then, where do you close the file you're reading from?
 - If you close it inside the exception block, you leak the file, since it
will not be closed on errors.
 - If you close it outside the exception block, then the problem is that
Close can raise an exception too, and the code gets uglier.
 - If you close it while handling exceptions, the exception you're handling
might have occured while opening the file, and closing a non-open file will
cause another exception.

So, are there any other possibilites, or which of these three is generally
considered the best?

Sergey.