actor-node source
actor-node actor#1 "a" @10:11
actor-node actor#2 "b" @11:11
actor-node sink
actor-edge source -> actor#1 exact count=2
actor-edge source -> actor#2 exact count=1
actor-edge actor#1 -> sink exact count=2 types="string"
actor-edge actor#2 -> sink exact count=1 types="string"
