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.