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From: " "@deneb.cygnus.argh.org (Florian Weimer)
Subject: Re: Handling exceptions to create an atomic operation
Date: 1999/12/12
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Robert A Duff <bobduff@world.std.com> writes:

> " "@deneb.cygnus.argh.org (Florian Weimer) writes:
> 
> > An operation which internally creates several objects should appear to
> > the caller as one operation which can either complete fail or succeed.
> 
> Consider using controlled types.

Something like the C++ auto_ptr template?  This sounds like a
good suggestion.  In fact, the code looks much cleaner now.  Thanks.

Limited types, however, seem to be a bit difficult to handle this way.
It's probably more reasonable to hack FLORIST to use controlled types
than to play with Unrestricted_Access (or even Unchecked_Access)...