在自定义定理环境中缩进段落

Question

问题：在我的自定义定理环境中，我希望定理环境中新段落的起始行紧跟其上方的行并缩进：

梅威瑟：

\documentclass{book}
\usepackage{amsthm}
\usepackage{enumitem}
\usepackage{xparse}
\usepackage{hyperref}

\usepackage{lipsum}

\newtheoremstyle{fctaylor}% name
  {\topsep}%      Space above
  {\topsep}%      Space below
  {\normalfont}%         Body font
  {}%         Indent amount (empty = no indent, \parindent = para indent)
  {\bfseries}% Thm head font
  {}%        Punctuation after thm head
  {\newline}%     Space after thm head: " " = normal interword space;
  {\makethmhead{#1}{#2}{#3}}

\newlength\fctaylortheoremindent
\AtBeginDocument{\setlength\fctaylortheoremindent{3em}} % <- customize here
\newlength\fctaylorlabelsep
\AtBeginDocument{\setlength\fctaylorlabelsep{1em}} % <- customize here

\makeatletter
\newcommand{\makethmhead}[3]{%
  \gdef\thisthmhead{%
    \makebox[\fctaylortheoremindent][l]{\bfseries#2}%
    {\bfseries#1}%
    \@ifnotempty{#3}{ (#3)}%
    \hspace{\fctaylorlabelsep}%
    \phantomsection%%% THIS LINE ADDED
  }%
}
\makeatother

\newenvironment{fctayloritemize}
 {\list{}{%
    \leftmargin=\fctaylortheoremindent
    \labelwidth=\dimexpr\fctaylortheoremindent-\labelsep\relax
    \itemindent=0pt
  }}
 {\endlist}

\NewDocumentCommand{\newfctaylortheorem}{smomo}{%
  \IfBooleanTF{#1}
   {\newtheorem*{fctaylor@#2}{#4}}
   {\IfNoValueTF{#3}
     {\IfNoValueTF{#5}
       {\newtheorem{fctaylor@#2}{#4}}
       {\newtheorem{fctaylor@#2}{#4}[#5]}}
     {\newtheorem{fctaylor@#2}[fctaylor@#3]{#4}}}%
  \NewDocumentEnvironment{#2}{o}
   {\IfNoValueTF{##1}{\begin{fctaylor@#2}}{\begin{fctaylor@#2}[##1]}%
    \begin{fctayloritemize}\item[\thisthmhead\hfill]}
   {\end{fctayloritemize}\end{fctaylor@#2}}%
}

\theoremstyle{fctaylor}
\newfctaylortheorem{thm}{Theorem}[section]
\newfctaylortheorem*{defn}{Definition}

\begin{document}
\section{One}

\begin{defn}
\lipsum*[2]
\end{defn}

\begin{thm}\label{A}
\lipsum*[2]
\end{thm}

\begin{thm}[Somebody]\label{B}
Something that should show how the text is split across line boundaries
and is correctly indented. And some equivalent conditions:
\begin{enumerate}[label=\upshape(\alph*),ref=(\alph*)]
\item a condition
\item another
\item and another
\end{enumerate}
which show the point made.

\indent\textbf{This line, which begins a new paragraph, should immediately follow the above line but be indented.}
\end{thm}

Here are the references: \ref{A} and \ref{B}.

\end{document}

我的工作：我尝试模仿一个答案到类似问题我尽我所能，通过改变

\newtheoremstyle{fctaylor}% 
  {\topsep}%
  {\topsep}%
  {\normalfont}%
  {}%
  {\bfseries}%
  {}%
  {0pt}%     Space after thm head: " " = normal interword space;
  {\makethmhead{#1}{#2}{#3}}

到

\newtheoremstyle{fctaylor}% 
  {\topsep}%
  {\topsep}%
  {\normalfont}%
  {}%
  {\bfseries}%
  {}%
  {\newline}%     The one thing I changed which seemed to work in the other answer
  {\makethmhead{#1}{#2}{#3}}

有什么想法可以完成我想要做的事情吗？（我只是尝试通过添加来修改有问题的行\indent，但这没有任何作用。）

Answer 1

您实际上是将定理/定义放入其中，list并将其标题显示为描述项。您设置此格式的方式看似复杂，我怀疑这是否是实现目标的最佳方式。

但是，根据您当前的代码，您所需要的只是\listparindent。不过，我还做了一些额外的调整：

• 没有必要使用\phantomsection。
• 我在关键的那一行之前补充\relax道。\itemindent=0pt\listparindent=\parindent
• 我删除\hfill了\item[\thisthmhead\hfill]。
• 由于我不完全理解您关于 的要求\newline，我\strut\par立即在 之后添加了\item[\thisthmhead]。这将导致标题后的文本排版在新段落中（\fctaylorlabelsep当然，这将变得毫无用处）。如果这不是您想要的，只需删除\strut\par。

再次，我想知道是否存在适合您的格式的更好的代码。

\documentclass{book}
\usepackage{amsthm}
\usepackage{enumitem}
\usepackage{xparse}
\usepackage{hyperref}

\usepackage{lipsum}

\newtheoremstyle{fctaylor}% name
  {\topsep}%      Space above
  {\topsep}%      Space below
  {\normalfont}%         Body font
  {}%         Indent amount (empty = no indent, \parindent = para indent)
  {\bfseries}% Thm head font
  {}%        Punctuation after thm head
  {\newline}%     Space after thm head: " " = normal interword space;
  {\makethmhead{#1}{#2}{#3}}

\newlength\fctaylortheoremindent
\AtBeginDocument{\setlength\fctaylortheoremindent{3em}} % <- customize here
\newlength\fctaylorlabelsep
\AtBeginDocument{\setlength\fctaylorlabelsep{1em}} % <- customize here

\makeatletter
\newcommand{\makethmhead}[3]{%
  \gdef\thisthmhead{%
    \makebox[\fctaylortheoremindent][l]{\bfseries#2}%
    {\bfseries#1}%
    \@ifnotempty{#3}{ (#3)}%
    \hspace{\fctaylorlabelsep}%
    %\phantomsection%%% THIS LINE ADDED% <-- This line commented out
  }%
}
\makeatother

\newenvironment{fctayloritemize}
 {\list{}{%
    \leftmargin=\fctaylortheoremindent
    \labelwidth=\dimexpr\fctaylortheoremindent-\labelsep\relax
    \itemindent=0pt\relax% <-- \relax added
    \listparindent=\parindent% <-- What you missed
  }}
 {\endlist}

\NewDocumentCommand{\newfctaylortheorem}{smomo}{%
  \IfBooleanTF{#1}
   {\newtheorem*{fctaylor@#2}{#4}}
   {\IfNoValueTF{#3}
     {\IfNoValueTF{#5}
       {\newtheorem{fctaylor@#2}{#4}}
       {\newtheorem{fctaylor@#2}{#4}[#5]}}
     {\newtheorem{fctaylor@#2}[fctaylor@#3]{#4}}}%
  \NewDocumentEnvironment{#2}{o}
   {\IfNoValueTF{##1}{\begin{fctaylor@#2}}{\begin{fctaylor@#2}[##1]}%
    \begin{fctayloritemize}\item[\thisthmhead]\strut\par}% <-- \hfill removed.
   {\end{fctayloritemize}\end{fctaylor@#2}}%
}

\theoremstyle{fctaylor}
\newfctaylortheorem{thm}{Theorem}[section]
\newfctaylortheorem*{defn}{Definition}

\begin{document}
\section{One}

\begin{defn}
\lipsum*[2]
\end{defn}

\begin{thm}\label{A}
\lipsum*[2]
\end{thm}

\begin{thm}[Somebody]\label{B}
Something that should show how the text is split across line boundaries
and is correctly indented. And some equivalent conditions:
\begin{enumerate}[label=\upshape(\alph*),ref=(\alph*)]
\item a condition
\item another
\item and another
\end{enumerate}
which show the point made.

\indent\textbf{This line, which begins a new paragraph, should immediately follow the above line but be indented.}
\end{thm}

Here are the references: \ref{A} and \ref{B}.

\end{document}

和\strut\par

没有\strut\par