Can't pass argument to second part of newenvironment

Question

This code works:

\documentclass{book}
\newenvironment{testenvironment}[1][]
    {\begin{quote}#1}
    {\end{quote}}
\begin{document}
\begin{testenvironment}[testargument]
test text
\end{testenvironment}
\end{document}

This code doesn't:

\documentclass{book}
\newenvironment{testenvironment}[1][]
    {\begin{quote}}
    {#1\end{quote}}
\begin{document}
\begin{testenvironment}[testargument]
test text
\end{testenvironment}
\end{document}

The only difference is whether #1 is written within the first vs. the second bracket of the \newenvironment command.

How do I pass the argument to the second bracket, to the content after the input?

Also related: https://tex.stackexchange.com/questions/17036/why-cant-the-end-code-of-an-environment-contain-an-argument — cabohah, Feb 17 '23 at 17:17

score 0 · Answer 1 · answered Feb 17 '23 at 17:19

With more recent LaTeX-releases you can use \NewDocumentEnvironment instead of \newenvironment.
You may need to load the package xparse.

\documentclass{book}
\usepackage{graphicx}
\NewDocumentEnvironment{testenvironment}{O{}}
    {\begin{quote}}
    {#1\end{quote}}
\begin{document}
\begin{testenvironment}[testargument]
test text
\end{testenvironment}
\begin{testenvironment}
test text
\end{testenvironment}
\begin{testenvironment}[testargumentB]
test text
\end{testenvironment}
\end{document}

Can't pass argument to second part of newenvironment

1 Answers1