Struct NodeResource 

pub struct NodeResource { /* private fields */ }

Backing for a node WIT resource: a path of Node::child indices from the tree root (empty = root), re-resolved against snapshot on each call.

Why the two caches (OA.0a)

The path is the identity, and re-resolving it walks from the root — the last step, Node::child(i), is O(i). So every accessor on the i-th child cost O(i), and named_child additionally rescanned the child list from zero on each call. Iterating one node’s k children was therefore O(k²), which made a guest tree walk quadratic in file size: a 34 KB org file took 29 seconds to scan, and the agenda it fed never arrived.

Both caches close that without changing the WIT or the guest:

• meta — this node’s own kind / range / flags, resolved at most once.
• children — one TreeCursor pass over the children, which is O(k) and answers named_child_count, named_child and child_by_field in O(1) thereafter. Each entry carries enough to seed the child’s own meta, so walking into a child resolves nothing at all.

A snapshot is immutable, so a cached answer cannot go stale.

Implementations

impl NodeResource

pub fn path(&self) -> &[u32]

The node’s root-relative child-index path — read by the host reset binding to reposition a cursor onto this node.

pub fn kind(&self) -> String

The node’s grammar kind (empty string if the path can’t resolve — never panics; an immutable snapshot always resolves).

pub fn is_named(&self) -> bool

pub fn is_error(&self) -> bool

pub fn byte_range(&self) -> NativeRange

The node’s [start, end) span as byte-columns per line (matching the native structural objects’ ProtoRange). A zero range if unresolved.

pub fn parent(&self) -> Option<NodeResource>

The parent node, or None at the root.

pub fn named_child_count(&self) -> u32

pub fn named_child(&self, index: u32) -> Option<NodeResource>

The index-th NAMED child, mapped to its child (all-children) index so the path stays in one indexing scheme.

pub fn child_by_field(&self, name: &str) -> Option<NodeResource>

The child under grammar field name (e.g. "body"), or None.

pub fn next_named_sibling(&self) -> Option<NodeResource>

pub fn prev_named_sibling(&self) -> Option<NodeResource>

pub fn walk(&self) -> CursorResource

TS.2: a walk cursor positioned at this node.