🚀 go-pugleaf

In article <1992Dec27.161533.11392@wam.umd.edu> joel@wam.umd.edu (Joel M. Hoffman) writes:

   I'd like to embed several \if\else\fi groups, but it doesn't seem to
   work.  For example

   \iftesta ...
	   \else ...
	   \iftestb
		   \iftestc ...
		   \fi
	   \else ...
   \fi

   I keep getting error messages about extra \else's.  I'm sure the
   \if's, \else's and \fi's are matches.

   I think what's might be happening is that TeX is ignoring the embedded
   \if's if the first test fails, and then seeing the embedding \fi, and
   thinking it matches the matrix \fi.  Is this so?  Is there a
   workaround?

This depends on what your \iftest.. are. Did you declare
them with \newif\iftesta? In that case TeX does keep track
of nesting just like you expect it would.

However, if you have defined
\def\iftesta#1#2{....... \ifx .....}
or something like that, TeX does not recognize your macro
as a conditional. Is there a work-around for this case? Yes!
In the next Tugboat I was going to mention a trick, devised
by the big K, and which I found in the TeX in Practice book
by Stephan von Bechtolsheim:
	\def\testa{00\fi ..... \ifx ..... }
to be used as
	\if\testa .....
Now TeX will skip such macros, while counting them as conditionals.

   -Joel

Victor.
--
Victor
``I have seen this funny quote, if only I could find it back.''