Struct ShadowTable 

pub struct ShadowTable { /* private fields */ }

Content-addressed shadow lookup table.

Entries are sorted by (scope, symbol, byte_offset). The chains index maps each (ScopeId, StringId) key to a half-open range [start, end) into entries. effective_binding does a backward linear scan through the relevant range to find the innermost definition before a query offset.

Serialization

Only entries is persisted. The chains index is derived from entries on deserialization and cannot drift out of sync. This keeps the V9 snapshot footprint minimal and eliminates the dual-write hazard.

Implementations

impl ShadowTable

pub fn new() -> Self

Creates an empty ShadowTable.

pub fn len(&self) -> usize

Returns the total number of shadow entries.

pub fn is_empty(&self) -> bool

Returns true if the table contains no entries.

pub fn entries(&self) -> &[ShadowEntry]

Returns the full sorted entries slice.

Useful for V9 persistence walkers, debug dumps, stats collection, and any future consumer that needs to iterate the entire table.

pub fn get(&self, id: ShadowEntryId) -> Option<&ShadowEntry>

Looks up a shadow entry by its dense ShadowEntryId.

Returns None if id.0 >= self.len(). The id is the position of the entry in the sorted slice, assigned during derive_shadows. It is stable for the lifetime of this table instance.

Used by resolution steps that record a shadow entry by id and later need to recover the full ShadowEntry.

pub fn shadows_in(&self, scope: ScopeId) -> Vec<&ShadowEntry>

Returns all shadow entries declared in scope, sorted by (symbol, byte_offset).

Returns an empty Vec when no entries belong to scope. The returned entries span all symbols in the scope, not a single symbol chain.

pub fn effective_binding( &self, scope: ScopeId, symbol: StringId, query_byte_offset: u32, ) -> Option<NodeId>

Returns the innermost shadow entry for (scope, symbol) whose byte offset is strictly less than query_byte_offset.

Returns None when no such entry exists — i.e., the query position is before the first definition of symbol in scope, or the (scope, symbol) pair has no entries at all.

Shadow semantics

This implements the Rust/JS/Python shadow semantic: a re-binding at offset B is visible only to references at offsets > B. The last definition strictly before the query offset wins.

Trait Implementations

impl Clone for ShadowTable

fn clone(&self) -> ShadowTable

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for ShadowTable

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

Formats the value using the given formatter.

impl Default for ShadowTable

fn default() -> ShadowTable

Returns the “default value” for a type.

impl<'de> Deserialize<'de> for ShadowTable

fn deserialize<D: Deserializer<'de>>(deserializer: D) -> Result<Self, D::Error>

Deserialize this value from the given Serde deserializer.

impl Serialize for ShadowTable

fn serialize<S: Serializer>(&self, serializer: S) -> Result<S::Ok, S::Error>

Serialize this value into the given Serde serializer.