Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!usc!jarthur!sif.claremont.edu
From: dhosek@sif.claremont.edu (Hosek, Donald A.)
Newsgroups: comp.text.tex
Subject: Re: Using \iffalse inside a LaTeX environment definition.
Message-ID: <7964@jarthur.Claremont.EDU>
Date: 27 Jul 90 19:36:35 GMT
Sender: news@jarthur.Claremont.EDU
Reply-To: dhosek@sif.claremont.edu
Organization: Harvey Mudd College
Lines: 47

In article <811@qusuntrd.queensu.CA>, erskine@qucis.queensu.CA (Neil Erskine) writes...
>	I have a large number of files written using LaTeX and some
>additional macros I wrote.  I sometimes want to suppress certain
>parts of them, so I thought to do this by placing some parts in null
>environments, as in

>\newenvironment{Comments}{}{}
>....
>\begin{Comments}
>Stuff that is sometimes suppressed.
>\end{Comments}

>I now want to suppress the comments, so I tried

>\newenvironment{Comments}{\iffalse}{\fi}

>but no dice, TeX (or LaTeX) won't take it.  The first time the
>Comments environment is used it complains of a missing \fi.  I suppose
>this is one of the standard questions that gets asked here, so don't
>flame too loudly; I just want a method that doesn't involve editing
>all those files.

Yes, this is a tricky problem, but there is a convenient way of
solving it given in verbatim.sty (get the file verbatim.readme
from ymir.claremont.edu in [anonymous.tex.inputs.latex-mainz] to
find out what files you will need. mailserv users can send a
message to mailserv@ymir.claremont.edu with the line
SEND [tex.inputs.latex-mainz]verbatim.readme
to get the list of necessary files). [[As an aside, let me point
out that the facilities provided in the latex-mainz directory
will become part of the next version of LaTeX which is why they
have been set aside in their own directory]]

If you have verbatim.sty you can then do something like

\newenvironment{answer}{\comment}{\endcomment} and have anything
between \begin{answer} and \end{answer} ignored. There are also
some very nice extensions of the verbatim environment and the
ability to do a verbatim input of another file.

-dh

---
Don Hosek                         TeX, LaTeX, and Metafont Consulting and
dhosek@ymir.claremont.edu         production work. Free Estimates.
dhosek@ymir.bitnet                
uunet!jarthur!ymir                Phone: 714-625-0147