seit gestern bekomme ich den Fehler File ended while scanning use of \XR@test beim Versuch, das folgende Dokument zu kompilieren:
\RequirePackage{xr-hyper} % muss vor dem Aufruf von beamer kommen!
\documentclass[ngerman]{beamer}
\usepackage{seminar}
\usepackage{xr-hyper}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% Titel %%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\author{Peter Pan}
\title[Kurz-Titel]{Titel}
\institute{Weltuniversität \\ Lehrgebiet Phantastik}
\date[Seminar XXX WS 2021/22]{22.06.2023}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% Folien des Hauptteils %%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\begin{document}
\section*{Titel und Gliederung}
% Titelseite:
\begin{frame}
\maketitle
\end{frame}
% Gliederung:
\begin{frame}<beamer>{Gliederung}
\def\jobname{seminar}%
\tableofcontents[pausesections,hideallsubsections]
\end{frame}
\begin{frame}<handout>{Gliederung}
\tableofcontents[hideallsubsections]
\end{frame}
\section{Definition Scheduling}
\subfile{template}
\section{Überblick Scheduling-Verfahren}
\subfile{template}
\section{Das Crown-Scheduling}
\subfile{template}
\section{Berechnung durch ILP}
%\subfile{template}
\end{document}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
Das template-Subfile sieht wie folgt aus:
\documentclass[seminar.tex]{subfiles}
%\usepackage{xr-hyper}
\externaldocument{seminar}
\begin{document}
\begin{frame}{??}
…
\end{frame}
\end{document}
Die komplette Fehlermeldung lautet wie folgt:
Runaway definition?
->\@writefile {nav}{\defcounter {refsection}{0}\relax }\@writefile {nav\ETC.
! File ended within \read.
<read 0>
l.4 \begin
{document}
This \read has unbalanced braces.
)
Runaway argument?
\@writefile {nav}{\headcommand {\slideentry {4} \par ...\XR@ }\begin \ETC.
! File ended while scanning use of \XR@test.
<inserted text>
\par
l.75 \subfile{template}
I suspect you have forgotten a `}', causing me
to read past where you wanted me to stop.
I'll try to recover; but if the error is serious,
you'd better type `E' or `X' now and fix your file.
! Missing } inserted.
<inserted text>
Der Fehler ! File ended while scanning use of \XR@test sagt mir auch leider überhaupt nichts.
Das .aux-File für seminar.tex habe ich mehrfach gelöscht und neu wieder aufbauen lassen, ebenso die .toc-Datei.
Für Tipps und Hinweise wäre ich sehr dankbar, ich komme hier gerade keinen Millimeter weiter.

