Fetches a specific in-edge slot in this node.
NOTE: When nodes are initialized, they must identify each of their InEdges with a unique ID. Our graph takes advantage of this method when rewiring edges between different nodes.
Unique identifier for the in-edge slot within this node.
A pointer to the identified in-edge, or null if it doesn't exist.
Fetches a specific in-edge slot in this node.
NOTE: When nodes are initialized, they must identify each of their InEdges with a unique ID. Our graph takes advantage of this method when rewiring edges between different nodes.