A unique ID for this node. Use this to identify nodes across edits via
OrgTree.edit, because OrgParentNodes can be recreated and thus will
not be equal via identical.
Find the first node in the AST that satisfies predicate. Specify a type
T to only visit nodes of that type. Returns a tuple of the node and its
path from the root of the tree, or null if no node is found.
Walk AST with visitor. Specify a type T to only visit nodes of that
type. The visitor function must return true to continue iterating, or
false to stop.