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From: Andrew Klaassen <clawsoon@my-dejanews.com>
Newsgroups: comp.lang.beta
Subject: Re: Speeding up BETA
Date: Tue, 04 May 1999 23:10:25 GMT
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In article <yz9u2tts2yl.fsf@grouleff.dk>,
  Morten Grouleff <morten.grouleff@mjolner.dk> wrote:
> Andrew Klaassen <clawsoon@my-dejanews.com> writes:
   ---snip---
> >
> > I tried a few other built-in BETA patterns;
   ---snip---
>
> Actually, they're not built-in in the language or the compiler, they are
> implemented in BETA in betaenv.bet and its BODY-fragments.
>

....mmm...yes. "Forgive us our trespasses against precise
terminology... "

   ---snip---
>
> > Are there good reasons _not_ to use a single object
> > instantiated from a built-in pattern, like the above, in
> > "real" programs?
>
> For patterns like putline, no. But the pattern must be able to handle
> it: Some patterns depend on the fact that their local attributes are
> initialized (to zero, empty string, false depending on the type).  This
> is done at allocation, so calling it twice might make such patterns
> behave badly.

Of course.  If I would have thought about this a wee smidge
before firing off my question, I would have remembered that
bit about local attributes being initialized to zero/false/
etc.

Looking through another comp.lang.beta thread ("Inconsistency
in the Mjoelner implemenation?"), I noticed that this
characteristic of BETA (or just of Mjolner BETA?) also makes
it difficult for the compiler to attempt the same kind of
optimization as I'm asking about here.

Is this question of "automatically initializing local
variables makes it more difficult for a compiler to decide
whether 'inserted objects' could be used to optimize code"
one that's debated when languages are designed? Is it just
an OO problem? A BETA problem?

(Sorry if the question violates the boundaries of this
newsgroup...or if the most appropriate response to it would
be, "There are schools that teach this sort of thing, you
know..." <G>)

>
> Regards,
> --
> **  Morten Grouleff:     <URL: http://www.grouleff.dk/>          **
> **  Earthworm Jim PC:    <URL: http://www.grouleff.dk/ewj.html>  **
> **  Mjølner Informatics: <URL: http://www.mjolner.com>           **
>

Thanks!
Andrew Klaassen

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