Trait datafusion::common::tree_node::TreeNodeIterator

pub trait TreeNodeIterator: Iterator {
    // Required methods
    fn apply_until_stop<F>(
        self,
        f: F,
    ) -> Result<TreeNodeRecursion, DataFusionError>
       where F: FnMut(Self::Item) -> Result<TreeNodeRecursion, DataFusionError>;
    fn map_until_stop_and_collect<F>(
        self,
        f: F,
    ) -> Result<Transformed<Vec<Self::Item>>, DataFusionError>
       where F: FnMut(Self::Item) -> Result<Transformed<Self::Item>, DataFusionError>;
}

Transformation helper to process a sequence of iterable tree nodes that are siblings.

Required Methods

fn apply_until_stop<F>(self, f: F) -> Result<TreeNodeRecursion, DataFusionError>

where F: FnMut(Self::Item) -> Result<TreeNodeRecursion, DataFusionError>,

Apples f to each item in this iterator

Visits all items in the iterator unless f returns an error or f returns TreeNodeRecursion::Stop.

Returns

Error if f returns an error or Ok(TreeNodeRecursion) from the last invocation of f or Continue if the iterator is empty

fn map_until_stop_and_collect<F>( self, f: F, ) -> Result<Transformed<Vec<Self::Item>>, DataFusionError>

where F: FnMut(Self::Item) -> Result<Transformed<Self::Item>, DataFusionError>,

Apples f to each item in this iterator

Visits all items in the iterator unless f returns an error or f returns TreeNodeRecursion::Stop.

Returns

Error if f returns an error

Ok(Transformed) such that:

1. transformed is true if any return from f had transformed true
2. data from the last invocation of f
3. tnr from the last invocation of f or Continue if the iterator is empty

Object Safety

This trait is not object safe.

Implementors

impl<I> TreeNodeIterator for I

where I: Iterator,