Predicate signature ApiGraphSharedSig::getSinkNode

Gets the sink node corresponding to node.

Since sinks are not generally LocalSourceNodes, such nodes are materialised separately in order for the API graph to include representatives for sinks. Note that there is no corresponding case for “source” nodes as these are represented as forward nodes with initial-state type-trackers.

Sink nodes have outgoing epsilon edges to the backward nodes corresponding to their local sources.