[Groff] Readable tbl-source

[Slotte Sverre (NRC/Helsinki)]

Hi

When cleaning out some old e-mail files I came upon an old question of 
mine: is it somehow possible to make the tbl-source "look OK" for 
easier editing? When elimiting fields with TAB or : or whatever fields 
of varying lengths make it difficult to see what is going on.

I originally sent this question to gnu.groff.bug in 1996, but I got no 
reply. Here we go again in a new forum:

-----------------------------------------------------------------
I am using gtbl to format a table. The fields of the table are of
varying length, and this makes it rather hard to read and edit:

    tab(:);     \" not mentioned in subsequent examples
    ...
    foo:bar:2:xxx
    this is a longer field:right!:89:xyzzy
    a:b:3:d

I came up with the (imho) novel idea on using ".char" (outside
the .TS/.TE pair) to create a filler character in order to put
some external structure into my table:

    .char _ \&

    foo_____________________:bar______:_2:xxx
    this is a longer field__:right____:89:xyzzy
    a_______________________:b________:_3:d

    .rchar _

This works beautifully; gtbl has no trouble formatting my table
correctly, and the source code is very readable.

In fact, I do not (normally) use standard characters, such as _,
but choose something out of the upper half of the latin1
character set. I am rather fond of the bullet character, since it
does not normally appear in text.

I have also used ".char _ \0" when I have needed a digit-wide
filler that does not occupy two spaces in the file.

My question is: is this a safe and acceptable way of using gtbl?
If not, why?

Would it even be possible to somehow map the space character
to \&, thus being able to write:

    .char _ \N'32'   \" This would output a real space

    foo                     :bar      : 2:xxx
    this_is_a_longer_field  :right    :89:xyzzy
    a                       :b        : 3:d

Eagerly awaiting responses from groff-gurus out there
-----------------------------------------------------------------

Regarding the question "is this a safe and acceptable way of using 
gtbl?" James Clark informed me that he "can't see any problem with it".

As for using spaces instead of e.g. _ I seem not to have received an 
answer, or then I just cannot find it anywhere.

Since groff is now under development again I should very much like to 
open this question again. Is there a batter way of achieving readable 
tbl-source than mapping rare characters to \&? Whitespace would be 
better, I think, but then we run into the problem with spaces and tabs 
apperaring quite legally in the text-fields.

Can something be done to gtbl to allow for source-code formatting? 
gpic does not have this problem, as it does not use whitespace in the 
same way (== formatting is possible).

Any thoughts out there?

Sverre

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