[Tex/LaTex] Article in biblatex with no year entry, how to remove parentheses

Question

For my bibliography I am using

\usepackage[maxnames=99,style=alphabetic,backend=bibtex]{biblatex}

I am using @article for arxiv papers. My problem is that I don't want to enter a year for such references. On the other hand, if I do not type in anything for the year, the generated bibliography prints () in place of the year.

How do I get rid of these parentheses?

Answer 1

Since year/date is a mandatory field for @article, biblatex expects there to be at least a year and does not do any further sanity checking to avoid empty brackets. We can add that with

\renewbibmacro*{issue+date}{%
  \ifboolexpr{not test {\iffieldundef{year}} or not test {\iffieldundef{issue}}}
    {\printtext[parens]{%
       \iffieldundef{issue}
         {\usebibmacro{date}}
         {\printfield{issue}%
          \setunit*{\addspace}%
          \usebibmacro{date}}}}
    {}%
  \newunit}

---

Note though that even papers on the arXiv normally have a year (at least I have yet to happen upon a paper without a date). You should also note that an arXiv paper that has not been published in a journal (if it was published, surely it will have a date) should not be treated as an @article, it should rather be an @online entry.