Re: [Groff] Strange error messages from Groff 1.22.3

[Doug McIlroy]

It is safe to convert backslashes to slashes only when it is
known that the literal string is indeed a file name. This
condition holds for command arguments, but not for groff
input text. "Fixing" .lf commands is of a piece with the
maddening AI of Microsoft Word and Open Office, which think
that they know what you mean.*

If .lf requests get fixed, should not .so requests be fixed too? 
What happens then to .so \*[input_file]? Treat \* differently
\f in context? And what if one doesn't use a preprocessor and has
defined .lf to mean something else?  Special cases multiply 
without end.

To return to my first sentence. It may be reasonable to canonicalize
file-name command arguments in groff and preprocessors. Once done,
no further special treatment is required, except at calls of the
Windows API, for which slashes must get rewritten, which apparently
happens already.

Doug

* For a ludicrous example, when I type my own name,
        M. Douglas McIlroy
at the beginning of a line--as for a signature or author line--
Open Office thinks that I've begun a paragraph numbered with
a Roman numeral, and proceeds to tack "MI." onto the beginning 
of the next line!

Groff has blessidly little AI. Let's keep it so.