XeLaTex Undefined control sequence []] with \twocolumn

Question

I'm using the IEEEconf documentclass. I want the abstract to span two columns directly after the title so I added the following:

\twocolumn[
    \begin{@twocolumnfalse}
        \maketitle
    \end{@twocolumnfalse}
    \vspace{2mm}
    \hrule
    \begin{abstract}
        abstract text.
    \end{abstract}
    \hrule
    \bigskip
]

When I build this with XeLaTex, I get the following error:

Undefined control sequence. []]

However, when I first comment out the lines with \twocolumn[ and ], keep the pdf open and build again, I keep getting the error, but the pdf is build normally. How can I prevent the error or tell XeLaTex to ignore this error?

Can you really use @twocolumnfalse outside a class or style file without \makeatletter? — Crissov, Feb 03 '14 at 16:16
I really don't understand, what you are doing. Usually you can write the text which you wish to have in one column just inside the []: \twocolumn[This will be printed in one column!] and this in two columns. OK, did not test, but write from memory, hopefully its true. — Keks Dose, Feb 03 '14 at 16:31
\twoculumn forces a pagebreak, that is why the maketitle is within the \twocolumn. The reason for the @twocolumnfalse environment is that \maktetitle already spans the two columns. See also here: http://www.tex.ac.uk/cgi-bin/texfaq2html?label=onecolabs and here: http://tex.stackexchange.com/a/140679so it should work. Maybe XeLaTex is the problem? — SeeDoubleYou, Feb 03 '14 at 20:11
It might help if you provided a proper compilable example people could play with. — Seamus, Feb 22 '16 at 13:48

score 0 · Answer 1 · answered Jan 23 '16 at 13:12

The following complete example gives no error with a current xelatex

\documentclass{IEEEconf}
\begin{document}
\title{zzz}
\author{z. zz}

\twocolumn[
    \begin{@twocolumnfalse}
        \maketitle
    \end{@twocolumnfalse}
    \vspace{2mm}
    \hrule
    \begin{abstract}
        abstract text.
    \end{abstract}
    \hrule
    \bigskip
]

aaa
\end{document}

score 0 · Answer 2 · answered Feb 22 '16 at 13:34

\documentclass{IEEEconf}
\author{Foo}
\title{bar}

\usepackage{blindtext}
\begin{document}
\twocolumn[
  \maketitle
  \hrulefill
  \abstract
  \blindtext
  \endabstract\par
  \vspace{-\medskipamount}
  \hrulefill
  \medskip
]

\blindtext
\end{document}

XeLaTex Undefined control sequence []] with \twocolumn

2 Answers2