Standalone documentclass gives errors

[pmeckoni]

Please extend support for standalone documentclass.
It currently gives errors.
I'm using TeX Live 2018 on Debian 10 Stable.

Below is the sample code that I used, which works well in article but not in standalone.

% \documentclass{standalone}
\documentclass{article}
\usepackage{optidef} %for optimization problems
\begin{document}
\begin{mini*}
{x}{ f (x)}{}{}
\addConstraint{x}{\le 9}{}
\addConstraint {x}{\ge 0}{}
\end{mini*}
\end{document}

[aravinat21]

use preview option like so:

\documentclass[preview]{standalone}
\usepackage{optidef} %for optimization problems
\begin{document}
\begin{mini*}
{x}{ f (x)}{}{}
\addConstraint{x}{\le 9}{}
\addConstraint {x}{\ge 0}{}
\end{mini*}
\end{document}