"Norton, Chris" wrote:
>
> Bob Arning [arning(a)charm.net] is rumored to have written:
>
> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> "I seem to remember some years ago using Smalltalk VSE on NT. Smalltalk
> garbageCollect or its equivalent reported some *really* large number, either
> gigabytes or 100's of megabytes (on a machine with 32 meg of real memory).
> When something started using too much memory, the closest indication one got
> was pronounced sluggishness and, if you listened closely, a disk drive
> earning its paycheck."
> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>
> That is my experience also with VSE (I've been using it for almost 6 years).
> One thing that VSE does that is really cool is that it returns a walkback
> quickly (stack overflow) when you have an infinite loop. I don't have the
> faintest idea how it does this, but I think Squeak could benefit greatly
> from this. Currently, if you accidentally code an infinite loop (e.g.
> method A calling method B, which calls method A), Squeak goes off into
> never-never land for a looooong time. Then it reports low space. If you
> accidentally abandon or close this walkback, your image gets hosed (well it
> hangs anyway). I hate it when this happens!
>
> If one of you excellent VM / Interpreter gurus would care to improve this
> behavior, I'd be very pleased! :-)
I see principal problems here, keyword 'Halteproblem' or how to compute if a
program stops. There isn't any general solution...
I think, the practical solution to press Alt-. isn't so bad, if you want to
interrupt a potentially endless loop.
In spite of this the behaviour in the walkback case could probably be
improved...
Greetings,
Stephan
>
> Cheers,
>
> ---==> Chris
--
Stephan Rudlof (sr(a)evolgo.de)
"Genius doesn't work on an assembly line basis.
You can't simply say, 'Today I will be brilliant.'"
-- Kirk, "The Ultimate Computer", stardate 4731.3