[metapost] groff support for MetaPost (and vice versa)

[Michail Vidiassov]

Dear Taco,

>> Thanks for the patch, but I cannot use this as-is, so it may be some
>> time before it gets integrated.
>> (Why did you break traditional troff support?)
>
> 1. We suspect that it has been non-functional for a longer time
>   already -- have you ever had a report from a person who actively
>   uses it?  Maybe we are wrong...
>
> 2. The `particular troff version' isn't specified: Is it AT&T troff?
>   Is it Sun troff?  Which version?
>
> 3. If you insist on retaining the old troff support it should be
>   rather straightforward to do so.  Please tell Michail because he
>   has written those changes.

I can add almost nothing to Werner's arguments.

Traditinal troff was not supported ;)

The old code worked with some "particular implementation",
that did not quite follow "Troff User's Manual" by Ossanna and Kernighan.
If you put back Changelog into mpware directory (it was dropped
for unknown reason at about 0.9) you may take a look at the record of 
2004-04-16.

After patches "particular implementation" becomes groff and not
"the Troff version found in Sun Solaris 2.x".

The main reason is lack of users.
Since the change mentioned above nobody complained.
teTeX 3 shipped with broken trfonts.map - nobody noticed
(including me).

You may include my e-mail in man page end error messages generated
by dmp. If someone gets problems trying to typeset metapost labels with
DWB or Plan 9 troff - I will react out of astonishment (at least).

               Sincerely, Michail