Struct TreeWalk 

pub struct TreeWalk<'cursor> { /* private fields */ }

A struct that walks through the current tree and calls the provided closure while traversing the tree.

Implementations

impl<'cursor> TreeWalk<'cursor>

pub fn on_field_id<T, const FIELD_ID: u16>( &mut self, result: &mut Result<Option<Arc<T>>, AstError>, ) -> ControlFlow<(), &mut TreeWalk<'cursor>>

where T: AstNode + for<'from> TryFrom<(&'from Node<'from>, &'from (dyn Database + 'static), &'from mut Builder, usize, Option<usize>), Error = AstError>,

Attempts to create an AST node of type T if the current cursor points to a field with the given ID.

If the field ID matches, the node is built and stored in result. Parsing then stops at this node. Returns ControlFlow::Break if a match is found and parsed, or Continue otherwise.

pub fn on_vec_field_id<T, const FIELD_ID: u16>( &mut self, result: &mut Vec<Arc<T>>, ) -> ControlFlow<(), &mut TreeWalk<'cursor>>

where T: AstNode + for<'from> TryFrom<(&'from Node<'from>, &'from (dyn Database + 'static), &'from mut Builder, usize, Option<usize>), Error = AstError>,

Like Self::on_field_id, but collects all matching nodes into a vector.

Parsing errors are accumulated into the database via ParseErrorAccumulator instead of propagating them.

pub fn on_children_id<T>( &mut self, result: &mut Result<Option<Arc<T>>, AstError>, ) -> ControlFlow<(), &mut TreeWalk<'cursor>>

where T: AstNode + for<'from> TryFrom<(&'from Node<'from>, &'from (dyn Database + 'static), &'from mut Builder, usize, Option<usize>), Error = AstError>,

Attempts to create an AST node of type T if the current cursor matches the T::contains predicate.

Useful for children without a specific field ID. The result is stored in result.

pub fn on_vec_children_id<T>( &mut self, result: &mut Vec<Arc<T>>, ) -> ControlFlow<(), &mut TreeWalk<'cursor>>

where T: AstNode + for<'from> TryFrom<(&'from Node<'from>, &'from (dyn Database + 'static), &'from mut Builder, usize, Option<usize>), Error = AstError>,

Like Self::on_children_id, but collects all matching nodes into a vector.

Errors are accumulated rather than returned, so the walk can continue through the tree.