01 August 2023

My PC was re-imaged several days ago. I upgraded texlive from 2021 to 2023, as it is not allowed to update packages in lower system version. In order to save disk space, this time I only install the packages I need to use.

But when I try to export one of my org-mode file to Beamer slides, the compilation reported errors:

! Extra \or.
\ifthenelse #1->\toks@ {#1}\TE@repl \or
                                        \TE@or \TE@repl \and \TE@and \TE@rep...
l.60 \end{frame}

! Emergency stop.
\ifthenelse #1->\toks@ {#1}\TE@repl \or
                                        \TE@or \TE@repl \and \TE@and \TE@rep...
l.60 \end{frame}

End of file on the terminal!

When I look into the tex file, l.60 is just the end of a frame:

\begin{frame}[label={sec:orgf852438}]{什么是 PA-DIM}

PA-DIM = Process Automation - Device Information Model \\[0pt]
过程自动化 - 设备信息模型
\item 过程自动化现场设备的常用参数
\item 统一的数据结构
\item 标准的数据语义
\end{frame} % this line

It looks fine. Later, I found a thread in stackexchange “why is the ifthen package obsolete?

The main reason why people may consider ifthen obsolete (last version is of 2001/05/26 with about one page of user manual plus four pages of code documentation) is that it is superseded by e.g. etoolbox, which uses the advanced possibilities of eTeX. Using these allows faster processing. You still can use ifthen for your existing and new documents if you like and I don’t think there is a risk in doing so. However for new code, especially new packages which use a lot of boolean expression using the more modern alternatives is recommended.

So I change my beamer template to use etoolbox, for example, I change from:




Then, texlive 2023 works fine.