how to remove this space in beamer + biblatex

Question

If I compile the following

\documentclass{beamer}
\usepackage[style=verbose]{biblatex}
\usepackage{filecontents}% to embed the file myreferences.bib in your .tex file
\begin{filecontents}{myreferences.bib}
@article{foo12,
  year = {2012},
  title = {Title},
  author = {H Miller},
  journal = {Journal}
}
\end{filecontents}
\addbibresource{myreferences.bib}
\AtEveryCitekey{
    \clearfield{pages}
    \clearfield{issn}
    \clearfield{doi}
    \clearfield{address}
    \clearfield{volume}
    \clearfield{isbn}
    \clearfield{series}
    \clearfield{number}
    \clearfield{note}
}
\begin{document}
\begin{frame}
Some text.\footnote{Some text in a footnote.} Some more text.\footcite{foo12}
\end{frame}
\begin{frame}
\printbibliography
\end{frame}
\end{document}

I get a big space between footnote label 2 and the citation. If I remove the \AtEveryCitekey block, the space goes away, and the two footnotes are aligned. Is this a bug? How can I get rid of the space while keeping the \AtEveryCitekey?

(Example adapted from here)

moewe · Accepted Answer · 2022-09-17T06:06:09.010

As explained in What is the use of percent signs (%) at the end of lines? (Why is my macro creating extra space?), TeX normally treats line ends just like spaces. Within \AtEveryCitekey spaces are relevant (essentially \AtEveryCitekey is like a \newcommand/\renewcommand on an internal macro that is called whenever biblatex processes a citation), so every line end ends up giving you a space in the citation output.

The solution is to hide the end of lines with %.

\documentclass{beamer}
\usepackage[style=verbose]{biblatex}
\AtEveryCitekey{%
    \clearfield{pages}%
    \clearfield{issn}%
    \clearfield{doi}%
    \clearfield{address}%
    \clearfield{volume}%
    \clearfield{isbn}%
    \clearfield{series}%
    \clearfield{number}%
    \clearfield{note}%
}
\begin{filecontents}{\jobname.bib}
@article{foo12,
  year    = {2012},
  title   = {Title},
  author  = {H Miller},
  journal = {Journal}
}
\end{filecontents}
\addbibresource{\jobname.bib}
\begin{document}
\begin{frame}
Some text.\footnote{Some text in a footnote.} Some more text.\footcite{foo12}
\end{frame}
\begin{frame}
\printbibliography
\end{frame}
\end{document}

how to remove this space in beamer + biblatex

1 Answers1