\begin{circus}
	\circchannel chan, chan2, chan3, chan4 : \nat
\end{circus}
\begin{circus}
	\circprocess A \circdef x : \nat \circspot \circbegin
		A1 \circdef 
			chan2.5 \then \Skip \extchoice 
			chan4.5 \then \Skip \\
		A2 \circdef (((chan.5 \then \Skip) \extchoice chan2.5 \then \Skip) \extchoice chan3.5 \then \Skip) \extchoice chan4.5 \then \Skip
		%\circspot A1 \lpar | \lchanset chan2 \rchanset | \rpar A2 \\
		\circspot A1 \interleave A2 \\
		\circend \\
\end{circus}
