Struct TreeContext 

pub struct TreeContext { /* private fields */ }

External parent-tracking context for an expression tree.

Since Rust’s ownership model does not allow intrusive parent pointers in the AST, TreeContext provides an on-demand side-table that maps each node (identified by a NodeId) to its ParentInfo (parent node, field name, and list index).

Build a context from any expression root with TreeContext::build, then query parent relationships with get, ancestry chains with ancestors_of, or tree depth with depth_of.

This is useful when analysis requires upward navigation (e.g., determining whether a column reference appears inside a WHERE clause or a JOIN condition).

Implementations

impl TreeContext

pub fn new() -> Self

Create a new empty tree context

pub fn build(root: &Expression) -> Self

Build context from an expression tree

pub fn get(&self, id: NodeId) -> Option<&ParentInfo>

Get parent info for a node

pub fn depth_of(&self, id: NodeId) -> usize

Get the depth of a node (0 for root)

pub fn ancestors_of(&self, id: NodeId) -> Vec<NodeId>

Get ancestors of a node (parent, grandparent, etc.)

Trait Implementations

impl Debug for TreeContext

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for TreeContext

fn default() -> TreeContext

Returns the “default value” for a type.