# Biblatex, emphasized/italic entries and redefined \emph{}

Many Biblatex-Styles use \mkbibemph{} to typeset italic parts of an bibliographic entry. By default, \mkbibemph{} is defined as \emph{}.

My Problem: If one redefines \emph{} like \renewcommand{\emph}[1]{\texttt{\color{red} #1}}, this breaks the intended appearance of the selected bib-style.

I tried to use \let\mkbibemph\mkbibitalic to avoid this, but had no success. I read Non-italic \emph, italic biblatex titles. Only setting the affected entries manually with

\DeclareFieldFormat[book]{title}{\mkbibitalic{#1}}
\DeclareFieldFormat[article]{journaltitle}{\mkbibitalic{#1}}


gave me the intended result (bibliographic entry in italic/'emphasized' AND a redefined \emph{} in the text). It looks like biblatex ignores its own \mkbibemph{} and uses \emph{} instead. The only alternative seems to be defining my own \emph{}.

This is not the behaviour I expect, is my understanding of how Biblatex works wrong? Can you point me to my mistake?

MWE below:

\documentclass{scrartcl}
\usepackage[latin1]{inputenc}
\usepackage[T1]{fontenc}

\usepackage[ngerman]{babel}
\usepackage{csquotes}
\usepackage{xcolor}
\usepackage{filecontents}
\begin{filecontents*}{\jobname.bib}
@article{small,
author = {Freely, I.P.},
title = {A small paper},
journal = {The journal of small papers},
year = 1997,
volume = {-1},
note = {to appear},
}

@article{big,
author = {Jass, Hugh},
title = {A big paper},
journal = {The journal of big papers},
year = 7991,
volume = {MCMXCVII},
}
\end{filecontents*}

\usepackage[bibstyle=authoryear,backend=bibtex8]{biblatex}

\usepackage{blindtext}

\renewcommand{\emph}[1]{\texttt{\color{red} #1}}
\let\mkbibemph\mkbibitalic      % overwrites \mkbibemph, but does not give the intended result

%% The only remedy I could find, uncomment to see intended result:
%\DeclareFieldFormat[book]{title}{\mkbibitalic{#1}}
%\DeclareFieldFormat[article]{journaltitle}{\mkbibitalic{#1}}

\begin{document}

\show\mkbibemph
\mkbibemph{\blindtext}\autocite{small}

\show\mkbibitalic
\mkbibitalic{\blindtext}\autocite{big}

\show\emph
\emph{\blindtext}

\printbibliography

\end{document}

• You would never redefine emph to be tt and coloured. Instead, you would define \newcomman{\megaimportant}[1]{\texttt{\color{red} #1}} and ask biblatex to use this for the places you want it. – Johannes_B Feb 26 '16 at 17:44
• Well that's not my point. I don't want to use \emph{} nor colored text in my refereces. The used markup for emph is just to show how biblatex apparently ignores it own (by me redefined) \mkbibemph, as I did not redefine \blx@imc@mkbibemph too as pointed out by @moewe. In my project intend to use a plain black \textsf{} :-). – Daniel Feb 26 '16 at 18:18

You don't only need to redefine \mkbibemph but also the internal macro \blx@imc@mkbibemph

\makeatletter
\renewrobustcmd*{\mkbibemph}{\mkbibitalic}
\protected\long\def\blx@imc@mkbibemph#1{\blx@imc@mkbibitalic{#1}}
\makeatother


But it is probably nicer to follow Johannes_B's advice and not redefine \emph, but use a really semantic command for your red emphasis.

• Thanks for the answer, this indeed helps me. The red was just for pointing to the unexpected behaviour. – Daniel Feb 26 '16 at 17:58
• What remains is the point that \emph is just logic markup (and not well definend as italic/textit) and it's weird to see that I have to stick with it. – Daniel Feb 26 '16 at 18:03
• @Daniel Mhhh yes, I think \emph is a bit of a bastardised command, it sounds semantic ("put emphasis on this"), but it is used so often as italic -> roman font switch that I would consider it risky to redefine it. – moewe Feb 26 '16 at 18:06
• @PatrickT I guess it is too late now. Changing that now would change the behaviour in many documents. People who insist on \textit can use \mkbibitalic or redefine \mkbibemph as above. I for one like the switching between italic and Roman that \emph gives me and can live with not redefining it and accept the weird semi-semantic status of \emph. – moewe Jun 5 '18 at 10:42
• @PatrickT Indeed \mkbibemph is just a wrapper around \emph (like \mkbibitalic is around \textit and \mkbibbold around \textbf). They do some additional bookkeeping for punctfont, but other than that just call the standard command. In cases like these it can be handy to look up the commands in the documentation, where this is explained (hopefully clearly enough). – moewe Jun 5 '18 at 10:57