Re: extra blank lines from @ifset inside @example

[Bob Wilson]

Karl Berry wrote:
> Sorry it's taken so long.  I just looked at your last report, and I
> can't actually reproduce it with your fragment -- see sample file below,
> which works ok with tug.org/ftp/tex/texinfo.tex.  So, can you send me
> something that causes the failure?  I don't really care how big it is,
> as long as it's something I can run TeX on directly.

You're right -- the problem no longer occurs, but the fix is not working very 
well, either.

I looked through the CVS revisions.  Here is what I found:

* 1.203: 9 Oct 2005: A potential fix that you also mailed to me.

* 1.204: 11 Oct 2005: You reverted the fix because I replied that it caused 
other problems.

* 1.205: 26 Dec 2005: This change ("make @/ a no-op in \pdfurl") included the 
following change to @doignoretext:

@@ -2963,8 +2978,11 @@
     % #1 contains the command name as a string, e.g., `ifinfo'.
     %
     % Define a command to find the next address@hidden #1', which must be on a 
line
-    % by itself.
-    address@hidden address@hidden
+    % by itself.  Ignore anything after the `#1'; this matters in
+    % verbatim environments, where otherwise the newline after an
+    % ignored conditional would result in a blank line in the output.
+    address@hidden #1##2^^M{%
+      address@hidden
     % And this command to find another #1 command, at the beginning of a
     % line.  (Otherwise, we would consider a line address@hidden @ifset', for
     % example, to count as an @ifset for nesting.)

I tried this change, and once again, it has a problem: some nested conditionals 
fail to parse.  The attached file demonstrates the problem.  The TeX output is:

(Problem sample))
Runaway argument?
@end ifclear^^M^^Mmore address@hidden
! File ended while scanning use of @next.
<inserted text>
                @par
<*> runaway.texi

?

\input texinfo
@setfilename runaway.info
@settitle Example of Texinfo Problem

@set A

@node Top
@top Problem sample

some text

@ifclear A
@ifclear B
ignored text
@end ifclear
@end ifclear

more text
@bye