Path: utzoo!attcan!uunet!nih-csl!keith
From: keith@nih-csl.UUCP (keith gorlen)
Newsgroups: comp.lang.c++
Subject: Re: Overloading operator new()
Summary: What does overloading new have to do with exception processing?
Message-ID: <797@nih-csl.UUCP>
Date: 7 Oct 88 20:01:23 GMT
References: <5949@june.cs.washington.edu> <294@itivax.UUCP>
Organization: NIH-CSL, Bethesda, MD
Lines: 25

In article <294@itivax.UUCP>, scs@itivax.UUCP (Steve C. Simmons) writes:
-> In article <5949@june.cs.washington.edu> david@uw-june.UUCP (David Callahan) writes:
-> >Could someone show me an example of "new" being overloaded and how
-> >it would be used?
-> 
-> Someone else has already posted how to do it.  I have no examples,
-> but can think of a good reason to do it -- exception handling.  Since
-> new allocates memory, there must be a way of doing garbage collection
-> should that allocation become unneeded due to an exception.  By overloading
-> new, you can go a long way to providing your own garbage collection
-> software and make use of more c-style exception processing.  Not perfect,
-> but a good step.

I don't see what operator new() has to do with exception handling in C++.  The main
problem with trying to do exception handling in C++ is that there doesn't seem to
be a good way to get the destructors called for auto objects that go out of scope
when an exception is raised.  operator new() is only used when allocating objects
on the free store with new, not when they are auto.  Could you please explain?
Thanks.

-- 
	Keith Gorlen			phone: (301) 496-5363
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