# Theorem linebreak in an itemize environment

I'm using the itemize environment to take notes and sometimes I want to add definitions and theorems in the flow.

However, amsthm adds a linebreak between the item bullet and the theorem statement, so they are not aligned.

Here's the fabled minimal working example :

\documentclass[11pt]{article}
\usepackage{amsthm}

\newtheorem{deff}{Definition}
\begin{document}
\begin{itemize}
\item In line.
\item \begin{deff}
This is not in line.
\end{deff}
\end{itemize}

\end{document}


Insert a manual vertical skip back to the baseline of the \item (a total of \baselineskip plus \topsep):

\documentclass[11pt]{article}

\usepackage{amsthm}
\newtheorem{deff}{Definition}

\begin{document}
\noindent
\begin{tabular}{@{}p{.48\linewidth}p{.48\linewidth}@{}}
\begin{itemize}
\item In line.
\item \leavevmode\par\vspace*{\dimexpr-\baselineskip-\topsep}\begin{deff}
This is in line.
\end{deff}
\end{itemize} &
\begin{itemize}
\item In line.
\item \textbf{Definition 1.} \itshape This is in line.
\end{itemize}
\end{tabular}

\end{document}


The tabular arrangement is merely to show the equivalence. I don't think there's much use/advantage is making this part of the definition of deff, as theorems are meant to usually stand on their own.

• Meh, I can't upvote your answer. Anyway thanks, it works fine, but I wish there was something more pretty than that. It's just that my document is all made of bullets of various depth (using the outline package). Also, I realized that it already worked when I don't import amsthm. – Literal Nov 1 '14 at 19:41
• @Neuschwanstein: If all you're using is a bunch of bullets and never setting a theorem (or deff) on a line of its own, then you could update the definition of deff by adding \let\olddeff\deff \renewcommand{\deff}{\leavevmode\par\vspace*{\dimexpr-\baselineskip-\topsep}\olddeff} to your document preamble. Now you can use it and it will always "jump up". – Werner Nov 1 '14 at 19:48