Variables: 
int[1]: "differ.x" 
int[2]: "differ.z" 
chan[1]: "A" 
chan[2]: "B" 

Event graph: 
event[0]: fork: null, #pred: 0, succ: 1 

# process[1]:
event[1]: receive: differ.L?(differ.x), pid: 1, #pred: 1, succ: 2 
channel deps: 1 
event[2]: receive: differ.L?(differ.z), pid: 1, #pred: 1, succ: 3 
channel deps: 1 
event[3]: send: differ.R!(differ.x-differ.z), pid: 1, #pred: 1, succ: 
channel deps: 2 

