Module datafusion::common::tree_node

This module provides common traits for visiting or rewriting tree data structures easily.

Structs

• Transformed
  This struct is used by tree transformation APIs such as

Enums

• TreeNodeRecursion
  Controls how TreeNode recursions should proceed.

Traits

• ConcreteTreeNode
  Instead of implementing TreeNode, it’s recommended to implement a ConcreteTreeNode for trees that contain nodes with payloads. This approach ensures safe execution of algorithms involving payloads, by enforcing rules for detaching and reattaching child nodes.
• DynTreeNode
  Helper trait for implementing TreeNode that have children stored as Arcs. If some trait object, such as dyn T, implements this trait, its related Arc<dyn T> will automatically implement TreeNode.
• TransformedIterator
  Transformation helper to process tree nodes that are siblings.
• TransformedResult
  Transformation helper to access Transformed fields in a Result easily.
• TreeNode
  Defines a visitable and rewriteable tree node. This trait is implemented for plans (ExecutionPlan and LogicalPlan) as well as expression trees (PhysicalExpr, Expr) in DataFusion.
• TreeNodeRewriter
  Trait for potentially recursively transforming a tree of TreeNodes.
• TreeNodeVisitor
  Implements the visitor pattern for recursively walking TreeNodes.