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From: gjr@hplgr2.hpl.hp.com (Guillermo (Bill) J. Rozas)
Subject: Re: R5RS?
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In-Reply-To: oz@nexus.yorku.ca's message of 5 Mar 96 13:24:56
Date: Wed, 6 Mar 1996 19:08:03 GMT
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In article <OZ.96Mar5132456@nexus.yorku.ca> oz@nexus.yorku.ca (ozan s. yigit) writes:

|   Guillermo (Bill) J. Rozas: [amongst other things]
|
|			   Things like off-by-one errors, inconsistent
|      shared data structures, non-terminating computations, race conditions,
|      etc. are far more devastating and I know of no simple tool that even
|      helps with them (not even worrying here about decidability).
|
|   but are these patchable during run time? cleanly? after off-by-one
|   error has taken its toll, or non-terminating computation has destroyed
|   last weeks computations, or the race condition caused the lossage?

No, I can claim to have a panacea.  I wish I did.

However, I have been able to overcome such bugs on the fly in many
situations.  Often enough, in fact, that I consider the ability to do
so invaluable.

I'm willing to believe that other people's experience differs.  I'll
let them defend their tools and modus operandi.  I will defend my own.

|   except for a few special cases, it is hard to make a good argument
|   for dynamic patching. real-world systems are often too complex to allow
|   an easy view of consequences, which is why weeks-long hard testing is
|   necessary. 

I agree that there is no substitute for testing.   However, I also
know that I have used dynamic patching on innumerable cases.
You may not have, or may not feel a need for it.  I do.
