On Mon, 14 Jan 2002, Rob Nagler wrote:
> > I'm afraid I don't get it - isn't it what the "finally" functionality
> > in Error.pm (CPAN) does ?
> >
> > try {
> > stuffThatMayThrow();
> > } finally {
> > releaseResources();
> > };
>
> One reason for exceptions is to separate error handling code from the
> normal control flow. This makes the normal control flow easier to
> read. If releaseResources() is to be called whenever an exception
> occurs, then it is advantageous to eliminate the extra syntax in the
> class's methods and just have releaseResources() called whenever an
> exception occurs and the object is on the stack.
>
> Our exception handling class searches down the stack looking for
> objects which implement handle_die(). It then calls
> $object->handle_die($die), where $die is the exception instance. This
> increases the cost and complexity of exception handling, while
> decreasing the cost and complexity of normal control flow. It also
> ensures that whenever the object is involved in an exception,
> handle_die() is called giving it an opportunity to examine the
> exception and clean up global state if necessary.
Might be a fun thing to try out using the mysterious PROPOGATE method (try
it - implement a PROPOGATE method in your exception class, and watch for
when it gets called).
--
<!-- Matt -->
<:->Get a smart net</:->
