biblatex backref – how to add spaces around the dash?

Question

I am using biblatex with backref=true, which generates ranges as e.g. 34–37. How can I make it e.g. 34 – 37? The spaces should be non-breakable.

I have tried to redefine \bibrangedash, but with no success.

Answer 1

Although the OP's question is about adding non-breakable spaces, I suggest a solution differing in two respects:

• As an en-dash surrounded by (full) spaces denotes the start/end of an insertion rather than a range, I'd use thin spaces instead.

• Because "line-breaking in the bibliography is often more difficult than in the body text and [...] you can not resort to rephrasing a sentence" (biblatex manual, section 3.8.4), the space following the en-dash should be associated with a high, but finite (for TeX, i.e., <10,000) penalty rather than unbreakable.

The corresponding biblatex commands are \addnbthinspace and \addhpthinspace. See section 4.7.4 of the manual for details.

\DefineBibliographyExtras{english}{
  \renewcommand*{\bibrangedash}{\addnbthinspace\textendash\addhpthinspace}
}

Answer 2

I was inattentive and misinterpreted a bit of the documentation. The following works, should someone need the same:

\DefineBibliographyExtras{english}{
\renewcommand*{\bibrangedash}{~\textendash~}
}