Nothing much
Get leaf or value with function get[R]

Method get[R] uses selector Leaf => R to produce a value R from leaf.
Make a few method to bind Tree and Clusters
Arrange text with Clusters approach instead of trees.
Move "Use" the operator into CFG
Dump position vectors and deltas
Implement SmartFile the class to alleviate access to files
Add a command to choose between tree and clusters