Re: Leaders

[Lennart Jablonka]

Quoth G. Branden Robinson:
> At 2023-09-02T22:35:25+0000, Lennart Jablonka wrote:
> > No, there aren’t.   Your message does not contain the SOH bytes;  you
> > could as well put replacement “^A”s there.
>
> I was attempting to suggest their presence.

My tone was too accusatory.   Yes, you did do that.   It worked 
for me.   I make the suggestion that you make it easier for the 
reader by using “^A.”

> > The point is that the width of the line of periods is determined by
> > its position on the input line.
>
> Yes, that's...what I guess we call "non-line-tabs mode".  Someone who
> hasn't posted here in a while suggested that we don't need names for
> modes like that, even (or especially?) when they're the default.
>
> > That is confusing, yet it also doesn’t usually matter:  You seldom use
> > tabs or leaders in filled text.
>
> Even if that is the case, we should explicitly specify the behavior, and
> document it in a way that is comprehensible to users.
>
> I challenge you to explain the following.

ok

> $ cat EXPERIMENTS/long-leader2.roff
> .ds ld \a\"
> .ta \n(.lu
> .nf
> .\" The default line length is 65n.
> 12345678901234567890123456789012345678901234567890123456789012345
> .fi
> The mansion into which my Val had ventured to make forcible
> entrance, rather than permit me, in my desperately wounded\*(ld
> .sp
> The mansion into which my Val had ventured to make forcible en-
> trance, rather than permit me, in my desperately wounded\*(ld
> .sp
> entrance, rather than permit me, in my desperately wounded\*(ld
> $ nroff EXPERIMENTS/long-leader2.roff | cat -s
> 12345678901234567890123456789012345678901234567890123456789012345
> The  mansion  into which my Val had ventured to make forcible en‐
> trance, rather than permit me, in my desperately wounded....

I would have expected the periods to continue until column 63.   
Three periods are missing.   Here, Heirloom troff does what 
I expect.   Yes, this seems like a bug in groff, though I am 
tempted to say something like “grotty is an approximation of the 
real output anyway;  what do you expect?”

If the three extra periods were there, it would be correct:  The 
number of periods would be the same as that of those in the third 
paragraph, as its input line is the same as this one.

> The mansion into which my Val had ventured to make  forcible  en‐
> trance, rather than permit me, in my desperately wounded........

This is correct:  You have a line in the input that appears 
unbroken as its own line in the output.   The leader ends at the 
tab stop.

> entrance, rather than permit me, in my desperately wounded.......

same here

> At least one of those must be wrong, don't you think?

Yes, the first one is off a little.