Struct LabelTable 

pub struct LabelTable { /* private fields */ }

String interning table for graph labels.

Stores each unique label string once and returns a compact LabelId that can be used for efficient comparison and storage.

Example

use velesdb_core::collection::graph::LabelTable;

let mut table = LabelTable::new();

// Intern same label multiple times - returns same ID
let id1 = table.intern("Person");
let id2 = table.intern("Person");
assert_eq!(id1, id2);

// Resolve ID back to string
assert_eq!(table.resolve(id1), Some("Person"));

Implementations

impl LabelTable

pub fn new() -> Self

Creates a new empty label table.

pub fn with_capacity(expected_labels: usize) -> Self

Creates a label table with pre-allocated capacity.

Arguments

• expected_labels - Expected number of unique labels

pub fn intern(&mut self, s: &str) -> Result<LabelId, LabelTableError>

Interns a string and returns its ID.

If the string was already interned, returns the existing ID. Otherwise, stores the string and returns a new ID.

Arguments

• s - The string to intern

Returns

The LabelId for this string (existing or newly created), or an error if the table has reached capacity (4 billion labels).

Errors

Returns an error if the number of interned strings would exceed u32::MAX.

pub fn resolve(&self, id: LabelId) -> Option<&str>

Resolves a LabelId back to its original string.

Arguments

• id - The LabelId to resolve

Returns

The original string, or None if the ID is invalid

pub fn len(&self) -> usize

Returns the number of unique labels in the table.

pub fn is_empty(&self) -> bool

Returns true if no labels have been interned.

pub fn iter(&self) -> impl Iterator<Item = (LabelId, &str)>

Returns an iterator over all interned labels.

pub fn get_id(&self, s: &str) -> Option<LabelId>

Gets the ID for a label if it exists, without interning.

Useful for lookup operations where you don’t want to add new labels.

pub fn contains(&self, s: &str) -> bool

Checks if a label is already interned.

Trait Implementations

impl Debug for LabelTable

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

Formats the value using the given formatter.

impl Default for LabelTable

fn default() -> LabelTable

Returns the “default value” for a type.