Forbid BibLaTeX to break URLs at hyphens

Question

By default, BibLaTeX will happily break lines at hyphens in URLs:
documentclass{article}
begin{filecontents}{main.bib}
@online{entry,
  title = {Title},
  subtitle = {Subtitle},
  author = {Doe, John},
  url = {http://some-quite-long-url-that-contains-hyphens},
}
end{filecontents}
usepackage{biblatex}
addbibresource{main.bib}
begin{document}
nocite{*}
printbibliography
end{document}

This can easily lead to confusion: was the hyphen added as a part of hyphenation, or is it a meaningful part of the URL? Therefore, I would like to forbid the hyphenation of URLs at hyphens.
BibLaTeX uses the url package, which does not break URLs at hyphens by default, and I see no mention about this behavior in the BibLaTeX documentation.

moewe · Accepted Answer

biblatex has its own URL setup in biburlsetup (ll. 285-324 of biblatex.def in v3.16). The default biburlsetup contains defUrlBigBreaks{do:do-}% and so explicitly allows line breaks at hyphens. We can undo that by changing UrlBigBreaks in apptobiburlsetup.
documentclass{article}

usepackage{biblatex}

apptobiburlsetup{%
  defUrlBigBreaks{do:}}

begin{filecontents}{jobname.bib}
@online{entry,
  title    = {Title},
  subtitle = {Subtitle},
  author   = {Doe, John},
  url      = {http://some-quite-long-url-that-contains-hyphens},
}
end{filecontents}
addbibresource{jobname.bib}
begin{document}
nocite{*}
printbibliography
end{document}

Of course not allowing to break URLs at hyphens can make many 'modern' URLs extremely hard to break at all. If a URL is typeset in a different font than the main text, most readers are probably warned that any hyphens appearing in the URL are real and not caused by hyphenation.

Ivan · Answer

You can add do- to UrlNoBreaks:
defUrlNoBreaks{do-do(do[do{do<}%

But as you can see from the example below in this way the url can not break and the result is ugly:

MWE
documentclass{article}
begin{filecontents}[overwrite]{main.bib}
 @online{entry,
  title = {Title},
  subtitle = {Subtitle},
  author = {Doe, John},
  url = {http://some-quite-long-url-that-contains-hyphens},
 }
end{filecontents}
usepackage{lipsum}
usepackage{biblatex}
addbibresource{main.bib}

defUrlNoBreaks{do-do(do[do{do<}%

begin{document}
lipsum[11]
 nocite{*}
 printbibliography
end{document}

Forbid BibLaTeX to break URLs at hyphens

2 Answers

Add your own answers!

Ask a Question