\: re-enables hyphenation--should it?

[G. Branden Robinson]

It seems that \: does more than I expected, and I'm wondering if that's
my fault or groff's fault.

Consider the following:

        .pl 1v
        .ll 1u
        .hy 4
        http://metathesis.com/foobar.html
        .sp 1v
        \%http://metathesis.com/foobar.html
        .sp 1v
        \%http://metathesis.com/\:foobar.html
        .sp 1v
        \%http://\:metathesis.com/\:foobar.html
        .sp 1v
        \%http://\:\%metathesis.com/\:\%foobar.html

Running this through "nroff -Wbreak", I get:

        http://metathe‐
        sis.com/foo‐
        bar.html

        http://metathesis.com/foobar.html

        http://metathesis.com/
        foo‐
        bar.html

        http://
        metathe‐
        sis.com/
        foo‐
        bar.html

        http://
        metathesis.com/
        foobar.html

Notice how hyphens return at the first possible point after a '\:' is
seen.

It appears that '\:' re-enables hyphenation.  I would expect hyphenation
to resume at the end of the word, but the word hasn't ended yet.
Without yet source diving, my guess is that the bit of state that '\%'
sets is cleared after a line break.

Arguably, it should not be.  Only (I think) the next actual word space
node should clear that bit of state.

If the above is correct behavior, then I need to update
makevarescape.sed in the source tree and the explanation and example of
\: in our Texinfo manual and man pages, because this detail is not
documented.

But I think it's a bug.

What do y'all think?

Regards,
Branden

signature.asc
Description: PGP signature