Struct lease::Pool

#[must_use]
pub struct Pool<T> { /* fields omitted */ }

A pool of objects of type T that can be leased out.

This struct implements std::iter::FromIterator so you can create it from an iterator by calling std::iter::Iterator::collect()

Implementations

impl<T> Pool<T>

pub fn new(pool_size: usize, init: impl FnMut() -> T) -> Self

Creates a new Pool with an initial size of pool_size by calling init pool_size times.

pub fn get_async(&self) -> AsyncLease<T>

Returns a future that resolves to a Lease when one is available

#[must_use]

pub fn get(&self) -> Option<Lease<T>>

Tries to get a Lease if one is available. This function does not block.

pub fn stream(&self) -> PoolStream<T>

Returns a struct that implements the futures_core::Stream trait.

pub fn get_or_new(&self, init: impl FnOnce() -> T) -> Lease<T>

Tries to get an existing Lease if available and if not returns a new one that has been added to the pool.

Calling this method repeatedly can cause the pool size to increase without bound.

pub fn get_or_new_with_cap(
    &self,
    cap: usize,
    init: impl FnOnce() -> T
) -> Option<Lease<T>>

Just like get_or_new() but caps the size of the pool. Once len() == cap then None is returned.

#[must_use]

pub fn len(&self) -> usize

Returns the size of the pool

pub fn clear(&self)

Sets the size of the pool to zero

This will disassociate all current Leasees and when they go out of scope the objects they’re holding will be dropped

pub fn resize(&self, pool_size: usize, init: impl FnMut() -> T)

Resizes the pool to pool_size

init is only called if the pool needs to grow.

pub fn associate(&self, lease: &Lease<T>)

Adds the Lease to this Pool if it isn’t already part of the pool.

#[must_use]

pub fn available(&self) -> usize

Returns the number of currently available Leasees. Even if the return is non-zero calling get() immediately afterward can still fail if multiple.

#[must_use]

pub fn is_empty(&self) -> bool

Returns true if there are no items being stored.

pub fn disassociate(&self, lease: &Lease<T>)

Disassociates the returned [‘Lease’] from this Pool

impl<T: Default> Pool<T>

pub fn get_or_default(&self) -> Lease<T>

Just like get_or_new() but uses Default::default() as the init function

#[must_use]

pub fn get_or_default_with_cap(&self, cap: usize) -> Option<Lease<T>>

Just like get_or_new_with_cap() but uses Default::default() as the init function

pub fn resize_default(&self, pool_size: usize)

Just like resize() but uses Default::default() as the init function

Trait Implementations

impl<T> Clone for Pool<T>

fn clone(&self) -> Self

Returns a copy of the value.

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

Performs copy-assignment from source.

impl<T> Debug for Pool<T>

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

Formats the value using the given formatter.

impl<T> Default for Pool<T>

fn default() -> Self

Returns the “default value” for a type.

impl<T> FromIterator<T> for Pool<T>

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

Creates a value from an iterator.