On Thu, Aug 8, 2024 at 7:59 AM Vincent Lefevre [off-list ref] wrote:

FYI, +-0 could be interpreted by the reader as in C, where a unary
minus operator is applied, then a unary plus operator. And about +/-0,
the "/" is already used a the division operator, so that this doesn't
help parsing.

It helps *some*, in that "/" can't be a unary operator, so it signals
to the reader that +/-0 isn't a C expression.  It also helps that
"+/-" has been used in other contexts where ± is unavailable, so some
readers might already be familiar with it.

The latter point argues in favor of Branden's idea to change groff's
fallback from +- to +/-.

So ideally, the fallback for "±0" should be "+0 or -0", which is
much more readable and less ambiguous than "+-0" or "+/-0".

That is a clearer phrasing, but unfortunately, there's no way to make
that transformation an automatic fallback in the man macros (unless
Tadziu swoops in to prove me wrong); the whole phrase would have to be
specifically coded that way in the individual page--something that,
aside from being discouraged in man pages, is less reliable than one
might hope (http://savannah.gnu.org/bugs/?65403#comment0).

Anyway, currently, for consistency, this should be "+0 or -0",
as this is already used:

...which luckily makes all the above moot.