Struct S3FifoWidthCache 

pub struct S3FifoWidthCache { /* private fields */ }

Width cache backed by S3-FIFO eviction (bd-l6yba.2).

Drop-in replacement for WidthCache that uses the scan-resistant S3-FIFO eviction policy instead of LRU. This protects frequently-used width entries from being evicted by one-time scan patterns (e.g. when a large block of new text scrolls past).

Uses the same 64-bit FxHash keying as WidthCache with a secondary FNV fingerprint for collision detection.

Implementations

impl S3FifoWidthCache

pub fn new(capacity: usize) -> Self

Create a new S3-FIFO width cache with the given capacity.

pub fn with_default_capacity() -> Self

Create a new cache with the default capacity (4096 entries).

pub fn get_or_compute(&mut self, text: &str) -> usize

Get cached width or compute and cache it.

pub fn get_or_compute_with<F>(&mut self, text: &str, compute: F) -> usize

where F: FnOnce(&str) -> usize,

Get cached width or compute using a custom function.

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

Check if a key is in the cache.

Keys on the 64-bit hash only (like WidthCache::contains): the fingerprint is not verified here, so a colliding string reports true even though get_or_compute would treat it as a miss.

pub fn stats(&self) -> CacheStats

Get cache statistics.

pub fn clear(&mut self)

Clear the cache.

pub fn reset_stats(&mut self)

Reset statistics.

pub fn len(&self) -> usize

Current number of cached entries.

pub fn is_empty(&self) -> bool

Check if cache is empty.

pub fn capacity(&self) -> usize

Total capacity.

Trait Implementations

impl Debug for S3FifoWidthCache

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

Formats the value using the given formatter.

impl Default for S3FifoWidthCache

fn default() -> Self

Returns the “default value” for a type.