Put a vertical line to separate 2 subgraphs

Question

I have one figure which contains 2 figures:

\begin{figure*}
  \begin{center}
    \subfigure[A]{
      \begin{tikzpicture}
      ....
      \end{tikzpicture}
    }
    \quad
    \subfigure[B]{
      \begin{tikzpicture}
      ....
      \end{tikzpicture}
    }
  \end{center}
\end{figure*}

Could anyone tell me how to add a vertical line between them to visually separate them?

Answer 1

Following the advice of percusse and egreg:

\documentclass{article}

\usepackage{tikz}
\usepackage{subcaption}

\begin{document}
\begin{figure}
    \centering
    \begin{tabular}{c|c}
        \begin{subfigure}[b]{0.45\textwidth}
            \centering
            \begin{tikzpicture}
                \fill[red] (0,0) rectangle (3,3);   
            \end{tikzpicture}
            \caption{A red square}
            \label{fig:red_square}
        \end{subfigure}
        &
        \begin{subfigure}[b]{0.45\textwidth}
            \centering
            \begin{tikzpicture}
                \fill[blue] (0,0) rectangle (3,3);      
            \end{tikzpicture}
            \caption{A blue square}
            \label{fig:blue_square}
        \end{subfigure}
    \end{tabular}
    \caption{Two squares}
    \label{fig:two_squares}
\end{figure}            
\end{document}