Struct IdCache 

pub struct IdCache<V> { /* private fields */ }

A cache keyed on node identity, dense: Vec<Option<V>> indexed by the id, so a lookup is a bounds check and NOT a hash.

This is the other half of hash-consing. Sharing makes a repeated subterm one node; a cache keyed on that node makes it checked ONCE.

Implementations

impl<V> IdCache<V>

pub fn new() -> Self

An empty cache.

pub fn get(&self, id: TermId) -> Option<&V>

The cached value for id, if any.

pub fn contains(&self, id: TermId) -> bool

Whether id has a cached value.

pub fn insert(&mut self, id: TermId, value: V)

Cache a value for id, replacing any previous one.

pub fn len(&self) -> usize

How many distinct ids are cached — the count that says “checked once, not once per occurrence”.

pub fn is_empty(&self) -> bool

Whether nothing is cached.

pub fn clear(&mut self)

Forget everything.

Trait Implementations

impl<V> Default for IdCache<V>

fn default() -> Self

Returns the “default value” for a type.