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From: Paul Winalski <paul.winalski@gmail.com>
To: Aron Insinga <aki@insinga.com>
Cc: coff@tuhs.org
Subject: [COFF] Re: ancient macros, machine code translation,as mental architecture models
Date: Mon, 15 Jul 2024 10:09:15 -0400	[thread overview]
Message-ID: <CABH=_VRYgiR107DGg9694owtvbCP3z0o7BTy_Wiv8o+=-56BSA@mail.gmail.com> (raw)
In-Reply-To: <980ed84f-8d93-4940-bd01-51bea7b10d18@insinga.com>

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On Sun, Jul 14, 2024 at 9:44 PM Aron Insinga <aki@insinga.com> wrote:

> I think that this may be (at least as far as any of us know) a unique case
> from the early days of computing where, on the TX-0 and a port to the
> PDP-1, a macro body *is* stored as a list of 'machine words' instead of
> source text.  The macro  body is not manipulated as a 'higher-level
> construct', it is just used for quite limited macro expansion.
>

Thanks for clearing this up.  I think you're right that this is a unique
case.  All assemblers I've ever dealt with expanded macros into text that
was then fed to the assember's parser just as if it were ordinary source
program text.  On a machine with limited memory it makes sense not to have
to re-parse the expanded source after macro expansion, but instead to do
the translation on the fly.  It saves a second pass over the expanded macro
call.

-Paul W.

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  reply	other threads:[~2024-07-15 14:09 UTC|newest]

Thread overview: 14+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-07-13 22:00 [COFF] " Douglas McIlroy
2024-07-13 23:46 ` John Levine
2024-07-14  0:54   ` Dan Cross
2024-07-14  1:04     ` Aron Insinga
2024-07-14  0:56   ` Aron Insinga
2024-07-14 18:02     ` [COFF] Re: ancient macros, " John Levine
2024-07-15  1:44       ` Aron Insinga
2024-07-15 14:09         ` Paul Winalski [this message]
2024-07-15 12:37 Douglas McIlroy
2024-07-15 14:26 ` Paul Winalski
2024-07-15 14:38   ` Bakul Shah via COFF
2024-07-15 19:39 ` John Levine
2024-07-16 19:55   ` Aron Insinga
2024-07-16 20:09     ` Aron Insinga

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