如何为 svmono 修补 samepage？

Question

继续为什么 \samepage 不设置 \predisplaypenalty （为 \@M 或任何其他值）？，假设我们想修补 LaTeX 的

\DeclareRobustCommand\samepage{\interlinepenalty\@M
   \postdisplaypenalty\@M
   \interdisplaylinepenalty\@M
   \@beginparpenalty\@M
   \@endparpenalty\@M
   \@itempenalty\@M
   \@secpenalty\@M
   \interfootnotelinepenalty\@M}

通过在\predisplaypenalty\@M某处添加（例如，因为您的类或包（比如，svmono.cls）设置\predisplaypenalty为小于的值\@M。）我们不打算\samepage直接使用而是\begin{samepage}…\end{samepage} 采用哪种方式？

我的尝试到目前为止都失败了。以下是一个失败的例子：

\documentclass{svmono}% version 5.10 (08-Sep-21); cf. http://www.springer.com/gp/authors-editors/book-authors-editors/your-publication-journey/manuscript-preparation#toc-49268 or http://resource-cms.springernature.com/springer-cms/rest/v1/content/20566/data/monographs
% at this spot we wish to redefine the samepage environment, but this one doesn't work:
\usepackage{etoolbox}
\makeatletter
\patchcmd{\samepage}{\interfootnotelinepenalty\@M}{\interfootnotelinepenalty\@M\predisplaypenalty\@M}{}{\typeout{samepage could not be redefined}}
\makeatother
\usepackage{amssymb,mathtools,cleveref}
\begin{document}
\begin{samepage}
  \strut\vskip120ex
  \begin{remark}[A remark name]\label[remark]{label}
    \[
      \text{a formula}
    \]
    \begin{center}%
      Table caption\\%%% probably better \nopagebreak\\ instead of \\, but anyway, samepage should better do all the job itself.
      \hbox to \hsize{\hfill
        \begin{tabular}[b]{|c|}
          \hline
          Some table\\
          \hline
        \end{tabular}%
        \hfill\llap{$\square$}}%
    \end{center}%
  \end{remark}%
\end{samepage}
\end{document}

产量

无法重新定义 samepage

在日志中并在备注中分页：

如何正确™ 扩展或重新定义samepage环境，以便我们不会在评论中出现分页符？

Answer 1

etoolbox无法修补使用 定义的命令\DeclareRobustCommand。您可以使用包xpatch将代码附加到带有 的强大命令中\xapptocmd。在这里您可以看到，补丁被使用了：

\documentclass{svmono}% version 5.10 (08-Sep-21); cf. http://www.springer.com/gp/authors-editors/book-authors-editors/your-publication-journey/manuscript-preparation#toc-49268 or http://resource-cms.springernature.com/springer-cms/rest/v1/content/20566/data/monographs
% at this spot we wish to redefine the samepage environment, but this one doesn't work:
\usepackage{xpatch}
\makeatletter
\xapptocmd{\samepage}{\predisplaypenalty\@M}{}{\PatchFailure}
\makeatother
\usepackage{amssymb,mathtools,cleveref}
\begin{document}
\begin{samepage}
  \strut\vskip120ex
  \begin{remark}[A remark name]\label[remark]{label}
    \verb|\predisplaypenalty| is \the\predisplaypenalty
    \[
      \text{a formula}
    \]
    \begin{center}%
      A table\\%%% probably better \nopagebreak\\ instead of \\, but anyway, samepage should better do all the job itself.
      \hbox to \hsize{\hfill
        \begin{tabular}[b]{|c|}
          \hline
          Some table\\
          \hline
        \end{tabular}%
        \hfill\llap{$\square$}}%
    \end{center}%
  \end{remark}%
\end{samepage}
\end{document}

但是如果你看一下整个内容，你还会发现，这并不能阻止头部之后的分页符remark：

甚至，如果你模式\begin{samepage} 后 \strut\vskip120ex你会得到相同的结果

所以你的问题的根源不是\predisplaypentalty。如果你真的不想在里面分页remark，我建议使用minipage：

\documentclass{svmono}% version 5.10 (08-Sep-21); cf. http://www.springer.com/gp/authors-editors/book-authors-editors/your-publication-journey/manuscript-preparation#toc-49268 or http://resource-cms.springernature.com/springer-cms/rest/v1/content/20566/data/monographs
% at this spot we wish to redefine the samepage environment, but this one doesn't work:
\usepackage{amssymb,mathtools,cleveref}
\begin{document}
  \strut\vskip120ex
\noindent\begin{minipage}{\textwidth}
  \begin{remark}[A remark name]\label[remark]{label}
    \[
      \text{a formula}
    \]
    \begin{center}%
      A table\\%%% probably better \nopagebreak\\ instead of \\, but anyway, samepage should better do all the job itself.
      \hbox to \hsize{\hfill
        \begin{tabular}[b]{|c|}
          \hline
          Some table\\
          \hline
        \end{tabular}%
        \hfill\llap{$\square$}}%
    \end{center}%
  \end{remark}%
\end{minipage}
\end{document}

如果您只是不想在开头有分页符remark，请使用包needspace。