polars_plan/plans/visitor/
mod.rs

1//! Defines different visitor patterns and for any tree.
2
3use arrow::legacy::error::PolarsResult;
4mod expr;
5#[cfg(feature = "cse")]
6mod hash;
7mod lp;
8mod visitors;
9
10pub use expr::*;
11pub use lp::*;
12pub use visitors::*;
13
14/// Controls how the [`TreeWalker`] recursion should proceed for [`TreeWalker::visit`].
15#[derive(Debug)]
16pub enum VisitRecursion {
17    /// Continue the visit to this node tree.
18    Continue,
19    /// Keep recursive but skip applying op on the children
20    Skip,
21    /// Stop the visit to this node tree.
22    Stop,
23}
24
25/// Controls how the [`TreeWalker`] recursion should proceed for [`TreeWalker::rewrite`].
26#[derive(Debug)]
27pub enum RewriteRecursion {
28    /// Continue the visit to this node and children.
29    MutateAndContinue,
30    /// Don't mutate this node, continue visiting the children
31    NoMutateAndContinue,
32    /// Stop and return.
33    /// This doesn't visit the children
34    Stop,
35    /// Call `op` immediately and return
36    /// This doesn't visit the children
37    MutateAndStop,
38}