Struct PersistentHashSet 

pub struct PersistentHashSet { /* private fields */ }

An immutable hash set that preserves insertion order when iterated.

Uses the same index-plus-ordered-log technique as PersistentHashMap: a rpds::HashTrieMap from value to insertion sequence number, and a rpds::RedBlackTreeMap from sequence number to value that is iterated in order. This keeps iteration deterministic and matching insertion order, rather than depending on hash-bucket layout — rpds seeds its hasher randomly per instance, so raw hash-order iteration would otherwise vary from run to run.

A set derived by conj or disj from a GC-allocated set reports only its path-copied nodes from gc_size_extra; see collections::share_charge for the full rule.

Implementations

impl PersistentHashSet

pub fn empty() -> Self

pub fn count(&self) -> usize

pub fn is_empty(&self) -> bool

pub fn contains(&self, val: &Value) -> bool

pub fn conj(&self, val: Value) -> Self

Return a new set with val added.

If val is already present, its original insertion position is kept.

pub fn conj_mut(&mut self, val: Value) -> &mut Self

pub fn disj(&self, val: &Value) -> Self

Return a new set with val removed.

pub fn iter(&self) -> impl Iterator<Item = &Value>

Iterate over all elements in insertion order.

Trait Implementations

impl Clone for PersistentHashSet

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for PersistentHashSet

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

Formats the value using the given formatter.

impl FromIterator<Value> for PersistentHashSet

fn from_iter<I: IntoIterator<Item = Value>>(iter: I) -> Self

Creates a value from an iterator.

impl PartialEq for PersistentHashSet

fn eq(&self, other: &Self) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl Trace for PersistentHashSet

fn trace(&self, visitor: &mut MarkVisitor)

fn gc_size_extra(&self) -> usize