Re: Look-ahead question

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#163

From: glen herrmannsfeldt
Date: Wed, 04 Oct 2006 18:40

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Edward Jaffe <edjaffe@phoenixsoftware.com> wrote:

> If you can foretell the future, can you then take steps to alter it?
> Such a conundrum/paradox might be fun to ponder while under the
> influence of mind-altering chemicals. But, in the real world of
> assembler language programming, a "crystal ball" seems like an
> unreasonable request to me.

It would be possible to do with more than two passes, though
I don't know of any assemblers that do it.

For assemblers, a similar problem comes up when deciding
between short and long branch instructions.

LaTeX has a related problem for doing table of contents and
other page references.  The LaTeX solution involves running
LaTeX multiple times, each time it reads in a file that it
previously wrote.  Usually this converges to the right solution
fairly fast, though there could be cases that don't converge.

-- glen

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From: glen herrmannsfeldt <gah@ugcs.caltech.edu>
Newsgroups: bit.listserv.asm370
Subject: Re: Look-ahead question
Date: Wed, 4 Oct 2006 11:40:37 -0700
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