\[
\newcommand{\tr}{\Rightarrow}
\newcommand{\trs}{\tr^{\!\ast}}
\newcommand{\rlnm}[1]{\mathsf{(#1)}}
\newcommand{\rred}[1]{\xrightarrow{#1}}
\newcommand{\rreds}[1]{\mathrel{\xrightarrow{#1}\!\!^*}}
\newcommand{\cl}{\mathsf{Cl}}
\newcommand{\pow}{\mathcal{P}}
\newcommand{\matches}{\mathrel{\mathsf{matches}}}
\newcommand{\kw}[1]{\mathsf{#1}}
\newcommand{\andop}{\mathrel{\&\!\&}}
\newcommand{\orop}{\mathrel{\|}}
\newcommand{\ff}{\mathsf{false}}
\newcommand{\tt}{\mathsf{true}}
\newcommand{\abra}[1]{\langle #1 \rangle}
\newcommand{\bnfnt}[1]{\abra{\small \textsf{#1}}}
\newcommand{\llbracket}{[\![}
\newcommand{\rrbracket}{]\!]}
\newcommand{\first}{\mathsf{First}}
\newcommand{\nullable}{\mathsf{Nullable}}
\newcommand{\follow}{\mathsf{Follow}}
\newcommand{\tm}[1]{\mathsf{#1}}
\]
\[\begin{align*}
&\textit{expression}_{\text{opt}}\textbf{;}\\
&\to \textit{expression}\textbf{;}\\
&\to \textit{assignment-expression}\textbf{;}\\
&\to \textit{unary-expression}\ \textit{assignment-operator}\ \textit{assignment-expression}\textbf{;}\\
&\to \textit{unary-expression}\ \mathbf{=}\ \textit{assignment-expression}\textbf{;}\\
&\to \textit{postfix-expression}\ \mathbf{=}\ \textit{assignment-expression}\textbf{;}\\
&\to \textit{primary-expression}\ \mathbf{=}\ \textit{assignment-expression}\textbf{;}\\
&\to \textit{identifier}\ \mathbf{=}\ \textit{assignment-expression}\textbf{;}
\end{align*}\]