Modify the dash in biblatex ibid

I'm using

\usepackage[backend=biber,style=authoryear-ibid]{biblatex}

Is it possible to modify the dash used in the bibliography to denote the same author by another symbol (e.g. a much longer dash)? Something like \renewcommand{\ibidendash}{\textemdash\textemdash}? The documentation shows how to turn off dashes, but not to modify them.

An example is the 50-style-authoryear.tex file.

• The command is \bibnamedash and is defined in biblatex.def (and described in the manual). You can redefine it. But note that it is a more complicated macro than you might guess. If you are using a 'contributed' style, they might redefine it also, so you should check. You will also probably need to adjust the \bibhang length to accommodate the longer dash length. It is a length, so you \setlength{\bibhang}{<length>}. – jon Apr 19 '15 at 3:36

Here's a version which uses a rule set to a fraction of the length of \bibhang

\documentclass{article}
\begin{filecontents}{\jobname.bib}

@book{Chomsky1986,
Author = {Noam Chomsky},
Publisher = {{MIT} Press},
Title = {Barriers},
Year = {1986}}

@book{Chomsky1981,
Author = {Noam Chomsky},
Publisher = {Foris Publications},
Title = {Lectures on Government and Binding},
Year = {1981}}
\end{filecontents}
\usepackage[style=authoryear-ibid]{biblatex}
\setlength\bibhang{.5in}
\renewcommand*{\bibnamedash}{%
\ifdimless{\leftmargin}{0.75em}
{\mbox{\textemdash\space}}
{\makebox[\leftmargin][l]{%
\ifdimless{\leftmargin}{1.25em}
{\textendash}
{\rule{.8\bibhang}{.2pt}}}}}
\begin{document}
\autocite{Chomsky1981,Chomsky1986}
\printbibliography
\end{document}


\setlength\bibhang{2.4em}%% two dashes and space
\renewcommand*\bibnamedash{\textemdash\textemdash\space}