Sub-Flows
Sub-Flows are nested flows inside a parent Flow, rendered as a SubFlowNode.
A SubFlowNode is a special type of Node that holds reference to another Flow (a nested flow) and proxies input/output data through its terminals to the inner flow's TunnelNodes.
Creating a SubFlow
Flow.addSubFlow
let subFlowNode = flow1.addSubFlow(flow2, Vector.create(200, 200));