At some point when working with a graph, you may want to create a linked list out of some nodes.
If each of the nodes to be linked has its own variable, this is easy, you just do a CREATE of the pattern using the node variables:
... // assume a, b, and c were previously matched and in scope CREATE (a)-[:REL]->(b)-[:REL]->(c)
You can of course break up a larger pattern into smaller ones, and use MERGE on the smaller patterns if needed, when there’s a possibility that a part of this linked pattern already exists.
However, when we don’t have separate variables for the nodes in question, such as if all of the nodes to link are under the same variable, or within a list, it’s not obvious how to link them.