Struct fn_cache::BTreeCache

pub struct BTreeCache<'f, I, O>where
    I: Ord,{ /* private fields */ }

A cache for a function which uses a BTreeMap.

The cache takes ownership of all inputs, but only passes a reference to the function, allowing it to store the input in the cache without any copies or clones.

The requirements for a BTreeMap must be met, specifically the keys must implement Ord

Implementations

impl<'f, I, O> BTreeCache<'f, I, O>where
    I: Ord,

pub fn new<F>(f: F) -> Selfwhere
    F: Fn(&I) -> O + 'f + Send + Sync,

Create a cache for the provided function. If the function stores references, the cache can only live as long as those references.

pub fn recursive<F>(f: F) -> Selfwhere
    F: Fn(&mut Self, &I) -> O + 'f + Send + Sync,

Create a cache for the provided recursive function. If the function stores references, the cache can only live as long as those references.

pub fn clear(&mut self)

Clears the cache, removing all key-value pairs. Keeps the allocated memory for reuse.

pub fn len(&self) -> usize

Returns the number of elements in the cache.

pub fn remove(&mut self, input: &I) -> Option<O>

Removes the input from the cache, returning any value if the input was previously in the cache.

Trait Implementations

impl<'f, I, O> FnCache<I, O> for BTreeCache<'f, I, O>where
    I: Ord,

fn get(&mut self, input: I) -> &O

Retrieve a value stored in the cache. If the value does not yet exist in the cache, the function is called, and the result is added to the cache before returning it.