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From: marcel@cs.caltech.edu (Marcel van der Goot)
Newsgroups: comp.text.tex
Subject: Re: A macro question (about variable number of args)
Message-ID: <1990Sep6.014900.11216@laguna.ccsf.caltech.edu>
Date: 6 Sep 90 01:49:00 GMT
References: <8208@jarthur.Claremont.EDU> <1990Aug29.002146.24426@agate.berkeley.edu>
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Reply-To: marcel@vlsi.caltech.edu
Organization: California Institute of Technology
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In <1990Aug29.002146.24426@agate.berkeley.edu> Carl Cotner
(cotner@math.berkeley.edu) asks for a way to write macros that take an
arbitrary number of arguments.


Here's how I usually do it (I don't remember whether this can be found
somewhere in the TeX-book; the idea was described to me several years
ago by Prof. R. Backhouse). I assume that the technique is pretty
well-known.

\def\callmymacro[#1+#2]% 
   {\mymacro{#1}%
    \def\more{#2}%
    \ifx\more\empty{}\else\callmymacro[#2]\fi
   }

\def\mynewmacro[#1]%
   {\callmymacro[#1+]%
   }

% The separator is '+'. You can call
%   \mynewmacro[input1+input2+input3]
% Try with, e.g., \def\mymacro#1{\immediate\write16{--- #1}}


					Marcel van der Goot
					marcel@vlsi.caltech.edu