\documentclass{minimal}
\begin{document}

\command{
  a
}{
  b
}

\begin{equation}
  \left(
    f(x) = 3
  \right)
  \left.
    f(x) = 3
  \right.
\end{equation}

{
  \graph[nodes={draw}
    test
  ]
}

\end{document}
