[Groff] Re: space and \~ in .tr request

[Werner LEMBERG]

I wrote:

> The similar request, as you all know,
> 
>   .tr \[xxx]
> 
> maps the character `xxx' onto the space character, or rather, it maps
> onto `\ ', i.e., an unpaddable, unbreakable space character. (Can
> someone please check this with AT&T troff?)  BTW, a real bug is that
> hyphenation (both implicit and explicit) doesn't work before the
> mapped space.  The original troff documentation says (in section
> 10.5):
> 
>   All text processing takes place with the input character which
>   appears to have the width of the final character.
> 
> But is this the ideal solution for a space character?
> 
> I would like to change groff's `.tr' implementation so that mapping a
> character onto a space is either a) or b):
> 
>   a) an unpaddable, breakable space character
>   b) a paddable, breakable space character
> 
> My favor is b).  Please tell me whether you have ever used mapping
> onto a space and which solution you prefer.  groff will of course
> emulate the original troff behaviour (whatever it is) while in
> compatibility mode.  I would also add `\ ' to the .tr request in case
> b) appears to be the right choice.

Unfortunately, I got no reaction from you all.  So I have to decide it
myself, and I will implement b).

If someone has access to UNIX troff, please test the behaviour so I
can do the right thing for compatibility mode.


    Werner