From: matz@... (Yukihiro Matsumoto)
Date: 2003-11-20T16:59:40+09:00
Subject: Re: Is there any way to throw an exception in a finalizer?

Hi,

In message "Is there any way to throw an exception in a finalizer?"
    on 03/11/20, Francis Hwang <sera@fhwang.net> writes:

|I'm trying to do write test code that involves a mock object throwing
|an exception on object destruction if a certain condition isn't met.
|(In particular, I want to guarantee that a class that uses DBI calls
|@dbh.disconnect.) I've been trying to set a finalizer with
|ObjectSpace.define_finalizer, but it seems like the GC doesn't want me
|to raise an exception from within a finalizer. Overall I understand --
|I probably wouldn't try anything this gnarly in production code -- but
|is there any way for me to get around this for test code?

You cannot assume when and where finalizers are called, and they are
not guaranteed to be called.  I don't think it's a good idea to raise
exception from within finalizers.

							matz.