autoryear-ext 与 introcite=label：从参考书目条目中删除额外的日期字母，但不从标签中删除

Question

我被要求制作一个作者年份格式的书目，标签中只有第一作者。如果标签太过激进，则会在年份后附加一个字母。这可以通过以下代码轻松制作（取自使用 biblatex 和 biber 创建具有固定缩进和作者年份标签的参考书目)：

\documentclass{article}
\usepackage[T1]{fontenc}
\usepackage[utf8]{inputenc}
\usepackage[british]{babel}
\usepackage{csquotes}
\usepackage[style=ext-authoryear, backend=biber, maxcitenames=1, uniquename=false, uniquelist=false, introcite=label, dashed=false]{biblatex}
\usepackage{filecontents}

\begin{filecontents*}{\jobname.bib}
  @book{Shepard2001a,
  author = {Shepard, Frank and Fisher, John},
  year = {2001},
  title = {Livestock management},
}
@book{Shepard2001b,
  author = {Shepard, Frank and Farmer, Boris},
  year = {2001},
  title = {On food supplies},
}
\end{filecontents*}
\addbibresource{\jobname.bib} % if you’re using biblatex\addbibresource{biblatex-examples.bib}

\setlength{\bibitemsep}{0.5\baselineskip plus 0.5\baselineskip}
\setlength{\introcitewidth}{6em}

\begin{document}
  \cite{Shepard2001a, Shepard2001b}
  \printbibliography
\end{document}

正如您所见，我正在使用ext-authoryearfrom biblatex-extwith introcite=label。

结果如下：

这很好，只是在参考书目条目中，应该删除附加在年份后面的字母。我用红线标记了“有问题的”字母。也就是说：我需要标签中的字母，但不需要参考书目条目本身中的字母。MWE 的条目应如下所示：

Shepard et al. 2001a
   Shepard, Frank and Boris Farmer (2001), ...

我不知道该在哪里改变它。

Answer 1

在宏中替换\printdateextra为：\printdatedata+extradate

\documentclass{article}
\usepackage[T1]{fontenc}
\usepackage[utf8]{inputenc}
\usepackage[british]{babel}
\usepackage{csquotes}
\usepackage[style=ext-authoryear, backend=biber, maxcitenames=1, uniquename=false, uniquelist=false, introcite=label, dashed=false]{biblatex}
\usepackage{filecontents}

\begin{filecontents*}{\jobname.bib}
  @book{Shepard2001a,
  author = {Shepard, Frank and Fisher, John},
  year = {2001},
  title = {Livestock management},
}
@book{Shepard2001b,
  author = {Shepard, Frank and Farmer, Boris},
  year = {2001},
  title = {On food supplies},
}
\end{filecontents*}
\addbibresource{\jobname.bib} % if you’re using biblatex\addbibresource{biblatex-examples.bib}

\setlength{\bibitemsep}{0.5\baselineskip plus 0.5\baselineskip}
\setlength{\introcitewidth}{6em}

\makeatletter
  \renewbibmacro*{date+extradate}{%
    \iffieldundef{labelyear}
      {}
      {\printtext[\blx@delimcontext labeldate]{%
         \iflabeldateisdate
           {\printfield{issue}%
            \setunit*{\addspace}%
            \printdate}
           {\printlabeldateextra}}}}%
  \renewbibmacro*{bbx:ifmergeddate}{\iflabeldateisdate}%
  \renewbibmacro*{issue+date}{%
    \usebibmacro{bbx:ifmergeddate}
      {}
      {\printtext[issuedate]{%
         \printfield{issue}%
         \setunit*{\addspace}%
         \printdate}}}
\makeatother

\begin{document}
  \cite{Shepard2001a, Shepard2001b}
  \printbibliography
\end{document}

Answer 2

日期打印的代码随所选mergedate设置而变化。预设为 ，mergedate=true相当于mergedate=compact，其中可以按如下方式进行修改。

\documentclass{article}
\usepackage[T1]{fontenc}
\usepackage[utf8]{inputenc}
\usepackage[british]{babel}
\usepackage{csquotes}
\usepackage[style=ext-authoryear, backend=biber,
  maxcitenames=1, uniquename=false, uniquelist=false,
  introcite=label, dashed=false]{biblatex}

\setlength{\bibitemsep}{0.5\baselineskip plus 0.5\baselineskip}
\setlength{\introcitewidth}{6em}

\makeatletter
\renewbibmacro*{date+extradate}{%
  \iffieldundef{labelyear}
    {}
    {\printtext[\blx@delimcontext labeldate]{%
       \iflabeldateisdate
         {\printdate}
         {\printlabeldate}}}}
\makeatother


\usepackage{filecontents}
\begin{filecontents*}{\jobname.bib}
  @book{Shepard2001a,
  author = {Shepard, Frank and Fisher, John},
  year   = {2001},
  title  = {Livestock management},
}
@book{Shepard2001b,
  author = {Shepard, Frank and Farmer, Boris},
  year   = {2001},
  title  = {On food supplies},
}
\end{filecontents*}
\addbibresource{\jobname.bib}

\begin{document}
  \cite{Shepard2001a, Shepard2001b}
  \printbibliography
\end{document}

另一个答案使用的代码作为mergedate=maximum基础，并重新定义了bbx:ifmergeddate和issue+date，尽管这不是必要的。在此处的代码中，我们还删除了extradate在 where 为 false 的情况下的信息\iflabeldateisdate。

---

另一个具有不同输出的选项是将authoryear引文与authortitle参考书目相结合。

\documentclass{article}
\usepackage[T1]{fontenc}
\usepackage[utf8]{inputenc}
\usepackage[british]{babel}
\usepackage{csquotes}
\usepackage[backend=biber, bibstyle=ext-authortitle, citestyle=ext-authoryear,
  sorting=nyt,
  maxcitenames=1, uniquename=false, uniquelist=false,
  introcite=label, dashed=false]{biblatex}

\setlength{\bibitemsep}{0.5\baselineskip plus 0.5\baselineskip}
\setlength{\introcitewidth}{6em}

\usepackage{filecontents}
\begin{filecontents*}{\jobname.bib}
  @book{Shepard2001a,
  author = {Shepard, Frank and Fisher, John},
  year   = {2001},
  title  = {Livestock management},
}
@book{Shepard2001b,
  author = {Shepard, Frank and Farmer, Boris},
  year   = {2001},
  title  = {On food supplies},
}
\end{filecontents*}
\addbibresource{\jobname.bib}

\begin{document}
  \cite{Shepard2001a, Shepard2001b}
  \printbibliography
\end{document}