我想创建一个带有一个可选参数的新环境，该参数用于设置 pgfkeys。我希望将一个键作为参数传递给枚举，以使项目一次出现一个（<+->）。似乎枚举将该参数作为计数器的样式（字母、阿拉伯语、罗马语……）。这是一个扩展问题吗？枚举是否在寻找特殊字符？我做错了什么？我也尝试过 l3keys，但遇到了同样的问题。
\documentclass{beamer}
\usepackage{xparse}
\usepackage{pgfplots}
\usepackage[T1]{fontenc} %%% without that the < > appear as inversed ! and ?
\pgfkeys{
/enume/.is family, /enume,
default/.style =
{opt = empty},
opt/.estore in = \theopt,
}
\NewDocumentEnvironment {myenum} {o} {%
\pgfkeys{/enume, default, #1}%
The key value is : \theopt
%\begin{enumerate}[<+->] % with this line it is working (but it doesn't use the parameter)
\begin{enumerate}[\theopt] % with this line it is not working
}{%
\end{enumerate}
}%
\begin{document}
\begin{frame}
\begin{myenum}[opt={<+->}]
\item I have a cat.
\item It is blue.
\end{myenum}
\end{frame}
\end{document}
答案1
想要enumerate看到明确的答案<，所以我们需要先扩展论点。
\documentclass{beamer}
\usepackage{xparse}
\usepackage{pgfplots}
\usepackage[T1]{fontenc} %%% without that the < > appear as inversed ! and ?
\pgfkeys{
/enume/.is family, /enume/.cd,
default/.style =
{opt = empty},
opt/.estore in = \theopt,
}
\NewDocumentEnvironment {myenum} {o} {%
\pgfkeys{/enume, default, #1}%
The key value is : \theopt
%\begin{enumerate}[<+->] % with this line it is working (but it doesn't use the parameter)
\edef\temp{\noexpand\begin{enumerate}[\theopt]} % with this line it is not working
\temp
}{%
\end{enumerate}
}%
\begin{document}
\begin{frame}
\begin{myenum}[opt={<+->}]
\item I am owned by a cat.
\item They are blue.
\end{myenum}
\end{frame}
\end{document}
