可以让 cleveref 使用牛津逗号进行多次引用吗？

Question

简单问题：有没有简单的方法可以cleveref使用牛津逗号？

\documentclass{article}
\usepackage[standard]{ntheorem}
\usepackage{cleveref}

\begin{document}

\begin{proposition}\label{thm:roses}
  Roses are red.
\end{proposition}

\begin{proposition}\label{thm:violets}
  Violets are blue.
\end{proposition}

\begin{proposition}
  42.
\end{proposition}

\begin{proposition} \label{thm:orchids}
  Orchids are orchid.
\end{proposition}

\begin{theorem}
  There exist flowers in at least three different colors.
\end{theorem}
\begin{proof}
  Immediate from \cref{thm:roses,thm:violets,thm:orchids}.
\end{proof}

\end{document}

应该说“命题1、2和4”。

Answer 1

如果你定义这个新命令

\newcommand{\creflastconjunction}{, and\nobreakspace}

无论你在哪里使用多个这样的引用，你都会看到牛津逗号。

梅威瑟：

\documentclass{article}
\usepackage[standard]{ntheorem}
\usepackage{cleveref}

\newcommand{\creflastconjunction}{, and\nobreakspace}

\begin{document}

\begin{proposition}\label{thm:roses}
  Roses are red.
\end{proposition}

\begin{proposition}\label{thm:violets}
  Violets are blue.
\end{proposition}

\begin{proposition}
  42.
\end{proposition}

\begin{proposition} \label{thm:orchids}
  Orchids are orchid.
\end{proposition}

\begin{theorem}
  There exist flowers in at least three different colors.
\end{theorem}
\begin{proof}
  Immediate from \cref{thm:roses,thm:violets,thm:orchids}.
\end{proof}

\end{document} 

输出：

---

附录

如果您想知道为什么必须使用\newcommand而不是renewcommand，这就是原因。

cleveref在文档开头定义了很多取决于语言的命令。如果您不指定任何语言，english则会加载。这是的相关部分cleveref.sty：

\DeclareOption{english}{%
  \AtBeginDocument{%
    ....
    \def\creflastconjunction@preamble{ and\nobreakspace}%
    ....

此外，您还可以找到以下几行

\AtBeginDocument{%
  ....
  \@ifundefined{creflastconjunction}{%
    \let\creflastconjunction\creflastconjunction@preamble%
  }{%
  ....
  }%

在文档的开头，当它还未被定义时，赋予\creflastconjunction其含义。\creflastconjunction@preamble

换句话说，\creflastconjunction得到定义仅有的之后\begin{document}。事实上，如果你尝试把这行

\newcommand{\creflastconjunction}{, and\nobreakspace}

在文档中，你会得到一个错误。在这种情况下，你应该写

\renewcommand{\creflastconjunction}{, and\nobreakspace}

Answer 2

简单回答：你可以使用

\newcommand{\creflastconjunction}{, and~}

来自手册：

\creflastconjunction用于两个以上交叉引用的倒数第二个和最后一个之间 [第 12 页，至少在我拥有的 2012-03-07 版手册中是这样的]

---

重做你的例子：

\documentclass{article}
\usepackage\[standard\]{ntheorem}
\usepackage{cleveref}

\newcommand{\creflastconjunction}{, and~}

\begin{document}

\begin{proposition}\label{thm:roses}
  Roses are red.
\end{proposition}

\begin{proposition}\label{thm:violets}
  Violets are blue.
\end{proposition}

\begin{proposition}
  42.
\end{proposition}

\begin{proposition} \label{thm:orchids}
  Orchids are orchid.
\end{proposition}

\begin{theorem}
  There exist flowers in at least three different colors.
\end{theorem}
\begin{proof}
  Immediate from \cref{thm:roses,thm:violets,thm:orchids}.
\end{proof}

\end{document}

Answer 3

您可以使用\crefmultiformat：

\documentclass{article}
\usepackage[standard]{ntheorem}
\usepackage{cleveref}

\crefmultiformat{proposition}{propositions~#2#1#3}%
  { and~#2#1#3}{, #2#1#3}{, and~#2#1#3}

\begin{document}

\begin{proposition}\label{thm:roses}
  Roses are red.
\end{proposition}

\begin{proposition}\label{thm:violets}
  Violets are blue.
\end{proposition}

\begin{proposition}
  42.
\end{proposition}

\begin{proposition} \label{thm:orchids}
  Orchids are orchid.
\end{proposition}

\begin{theorem}
  There exist flowers in at least three different colors.
\end{theorem}
\begin{proof}
  Immediate from \cref{thm:roses,thm:violets,thm:orchids}.
  Immediate from \cref{thm:roses,thm:violets}.
\end{proof}

\end{document}