[tex-eplain] Bug(?) in \newcommand

[Daniel Henry Luecking]

Hello:

The definition of \newcommand in eplain eventually invokes \@newcommand 
(see below). This atempts to \edef the macro and leads to errors in simple cases:

\input eplain
\newcommand\y{\gobble}
\bye

Of course the error is 
    ! Argument of \gobble has an extra }
But this is certainly a valid way to define \y, as long as one 
does not try to expand its replacement text. 

The definition of \newcommand comes from btxmac.tex, so perhaps 
there is a reason for bibliographies to use \edef. I have never 
used \newcommand in \eplain directly. I only encountered the error 
when a supposedly plain.tex compatible file performed a test
 \expandafter\ifx\csname newcommand\endcsname\relax
and then tried to \newcommand something instead of \def-ing it.

The questionable eplain.tex/btxmac.tex code follows. The \edef 
occurs in the first line of \@newcommand, but is only invoked 
in the last one:
\def\@newcommand#1{%
   \def\@startdef{\expandafter\edef\@commandname}%
%
% The remainder of this long definition is irrelevant.
%
  \expandafter\@startdef\@paramdef{#1}%
}%

Dan

Daniel H. Luecking
Department of Mathematical Sciences
University of Arkansas
Fayetteville, Arkansas