Re: GNU eqn clarifications and reforms

[Damian McGuckin]

On Sat, 17 Jun 2023, Douglas McIlroy wrote:

> $$ is etched into my fingertips;

Mine too.

> @@ is the fallback when I need to 
> protect $1 and the like, typically for pic code that contains its own 
> macros together with eqn constructs.
>
> ## has the virtue of not colliding with other eqn constructs
> or with groff macro definitions. It does collide with groff
> color specs and \# comments and with pic comments, so
> it's not a panacea, but seems better than $$.
>
> @@ may deserve consideration. The only collisions that
> come to mind are with the esoteric groff escape \$@.and
> with mentions of email addresses or shell scripts.
> Unfortunately, it is visually intrusive.

Wow. That's great. Can I just use that as-in and put a reference to a
private communication.
> You may also want to make a recommendation for delimiting bodies of eqn 
> macros. I use %%--not perfect, but any conflicting groff constructs will 
> be right there in full view.

Sounds like a good idea.

Thanks - Damian

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