Newtheorem 在定理名称前添加一个空格

Question

如何删除定理名称前面插入的空格？即括号左侧的空格。我希望括号左对齐。

由于某种原因，我无法理解该\newtheoremstyle命令。

\documentclass{beamer}
\usepackage[english]{babel}

\theoremstyle{definition}
\newtheorem{mydef}{}[theorem]

\begin{document}
\begin{frame}
\noindent Here is a sentence with correct alignment
\begin{mydef}[This name is prefixed by a single space]
This is a definition 
\end{mydef}
\noindent Here
\end{frame}
\end{document}

Answer 1

通常在定理名称和附加文本之间有一个硬编码空格。要删除此空格，您可以重新定义模板theorem begin：

\documentclass{beamer}
\usepackage[english]{babel}

\theoremstyle{definition}
\newtheorem{mydef}{}[theorem]

\makeatletter
\setbeamertemplate{theorem begin}
{
  \normalfont
  \begin{\inserttheoremblockenv}
  {%
    \inserttheoremname%
    \ifx\inserttheoremaddition\@empty\else%\ <- Removed this space
    (\inserttheoremaddition)\fi%
  }%
}

\makeatother

\begin{document}
\begin{frame}
\noindent Here is a sentence with correct alignment
\begin{mydef}[This name is prefixed by a single space]
This is a definition 
\end{mydef}
\noindent Here
\end{frame}
\end{document}

Answer 2

一个解决方案..但在接受之前请等待更好的答案：

\documentclass{beamer}
\usepackage[english]{babel}
\usepackage{tikz}
\def\tikzmark#1{\begin{tikzpicture}[remember picture]\coordinate (#1);\end{tikzpicture}}
\theoremstyle{definition}
\newtheorem{mydef}{\hskip-0.375em}[theorem]% Here is the only change needed

\begin{document}
\begin{frame}
 \tikzmark{A}Here is a sentence with correct alignment

  test
\begin{mydef}[This name is prefixed by a single space]
This is a definition 
\end{mydef}
\tikzmark{B}Here
\begin{tikzpicture}[overlay,remember picture]
  \draw[red,-] ([yshift=1em]A)--(B);
\end{tikzpicture}
\end{frame}
\end{document}