Re: *roff hyphenation trivia challenge

[Tadziu Hoffmann]

> Groff already *does* ignore correct hyphenation points,
> namely before the first "\%" (but allows them afterward).
>
> My concern is that if "\%" only allows specifying
> *additional* hyphenation points, then we have no method
> of forbidding hyphenation points that the patterns
> incorrectly allow.

I'm revising my empirical description of groff's behavior.

Groff allows normal hyphenation after the *last* "\%" in
the word.  Thus, if we end the word with "\&\%", it has the
effect of only allowing hyphenation at any of the "\%" given.
(If the word contains no "\%" other than the trailing "\&\%",
the effect is the same as preceding the word with "\%", i.e.,
hyphenation is suppressed in this occurrence of the word.)

The behavior feels weird, but I'm satisfied that my
requirements can be fulfilled using this trick.