Re: [Groff] Tips & Tricks: Tables with abutting rules

[Ingo Schwarze]

Hi Werner,

Werner LEMBERG wrote on Thu, Jul 07, 2011 at 08:09:23PM +0200:
> Ingo Schwarze wrote:
>> Werner Lemberg wrote:
>>> Ted Harding wrote:

>>>> There is no 'tbl' option which allows a "no space" to be set in
>>>> this context.  However, there is a trick.  This is to use dummy
>>>> columns at the left and/or right, with associated zero column
>>>> spacings.  [...]

>>> Very nice!  Could you convert this small tutorial into something
>>> which I can add to the tbl manpage?

>> Ugh.  This looks like an extremely ugly hack abusing tbl(1) in a way
>> it was never meant to be used.

> ???  I strongly disagree.

This was strongly overstated due to the misunderstanding below,
but it still doesn't seem very robust across output devices
even with groff-1.21:

$ /usr/local/bin/tbl colspace.tbl | /usr/local/bin/nroff -Tascii -c     
 |  two words   |
 and three words|

Note that even newest and shiniest grotty produces an unintended
one-column indent and hides the left border line behind the text.
That _is_ the consequence of using an edge case feature, i think.

Compared to the standard '|c|' as given by Ted:

$ /usr/local/bin/tbl col.tbl | /usr/local/bin/nroff -Tascii -c 
|   two words    |
|and three words |

... which looks just fine.

>> In general, you are better off in programming if you avoid using
>> counter-intuitive quirks near the borders of languages (in this case,
>> empty columns and mixing low-level roff with high-level tbl).

> Where is low-level roff?  In the table shown by Ted, namely
>
>   .TS
>   tab(#);
>   r0|c0|l.
>   #two words#
>   #and three words#
>   .TE
> 
> I only see high-level tbl code.

Err, yes, sorry for the confusion, i somehow misread the
comparison roff code as part of the example.
So that part is settled.

Yours,
  Ingo