Message-Id: <9309171404.AA27478@sc.ZIB-Berlin.DE>
Reply-To: Mailing list for the LaTeX3 project <LATEX-L@vm.urz.Uni-Heidelberg.de>
Date:         Fri, 17 Sep 93 09:45:31 EDT
From: Michael Barr <barr@TRIPLES.MATH.MCGILL.CA>
Sender: Mailing list for the LaTeX3 project <LATEX-L@vm.urz.Uni-Heidelberg.de>
To: Multiple Recipients of <LATEX-L@vm.urz.Uni-Heidelberg.de>
Subject:      Re: Latex-l `problem': can you fix this sometime, thanks
Status: R


> Paul Taylor wrote in response to a message from me:
>
>  > Rainer says, in response to the \par-redefinition bug:
>  > > it doesn't prevent people from using these primitive commands.
>  > > If the box [had] been produced by \makebox or \parbox, there
>  > > would have been no infinite loop. (the other possibility would be to
>  > > insert \@parboxrestore at the beginning of the box construction.)
>  >
>  > I'm sorry Rainer, but (with the greatest respect) I don't like your answer
>  > at all. Of course in a *document* written in LaTeX one should use LaTeX's
>  > idiom, but the problem (whatever it is) might arise in a macro package.
>
> Exactly.
>
>  > What you are saying is that macros may only be used with LaTeX if they
>  > conform exactly to you standards and (which is the point) they rely on LaTeX.
>
> No, I was saying that *documents* have to rely on LaTeX only. Sorry
> for not being clear enough. If a macro in a macro package conflicts
> with the inner workings of LaTeX, then
>
> (1) it needs to be changed to work with LaTeX, or
> (2) it exhibits a problem with LaTeX itself, or
> (3) both of the above.
>
> My point is that failure to cope with LaTeX's redefinition of \par is
> of type (1).
>
> Rainer Sch"opf
>

If I may be permitted to add my 2 sous here, I would like to say
that although I agree with RS's answer, I do regard it as a definite
defect in tex (not plain, not latex, but tex) that a tex primitive
depend on another tex primitive when the latter can be redefined.
If \vfill were a \def'ined term, then you could \let\Par\par and
then redefine \vfill using \Par.  But the dependency is built in and
cannot be overcome so easily.

Michael Barr