freepascal.compiler/docs/syntax/typeintf.syn

\begin{diagram}{Interface type}{interfacetype}
\begin{mysyntdiag}
\lit*{Interface} 
\begin{stack}\\ heritage \end{stack}
\begin{stack}\\ \lit*{['} GUID \lit*{']} \end{stack}
\begin{stack}\\ 
\synt{component\ list} 
\end{stack}
\lit*{end} 
\end{mysyntdiag}
\begin{mysyntdiag}
\synt{heritage} \lit*( \synt{interface\ type\ identifier} \lit* )
\end{mysyntdiag}
\begin{mysyntdiag}
\synt{component\ list} 
  \begin{rep}[b] 
    \begin{stack} 
      \synt{method\ definition} \\
      \synt{property\ definition}
    \end{stack} \\ 
  \end{rep} 
\end{mysyntdiag}
\end{diagram}