Struct LocalPollAdapter 

pub struct LocalPollAdapter<'a, S, K, R> {
    pool: FuturesUnordered<LocalBoxFuture<'a, (K, R)>>,
    cache: HashMap<K, Poll<R>>,
    self_parameter: S,
}

A local (!Send) adapter for caching and executing an async method from a non-async context.

The self_parameter, key, and successful (Ok) results must all be cheap to clone.

Ensures at most one in-flight computation per key. Results are:

• cached on success
• not retained on error

Fields

pool: FuturesUnordered<LocalBoxFuture<'a, (K, R)>>

cache: HashMap<K, Poll<R>>

self_parameter: S

Implementations

impl<'a, S, K, V, E> LocalPollAdapter<'a, S, K, Result<V, E>>

where S: Clone + Deref + 'a, K: Clone + Hash + Eq + 'a, V: Clone,

pub fn new(self_parameter: S) -> Self

pub fn poll<F>(&mut self, f: F, key: K) -> Poll<Result<V, E>>

where F: AsyncFn(&S::Target, &K) -> Result<V, E> + 'a,

Polls the result for key, spawning work if needed.

If this function returns Poll::Pending, call LocalPollAdapter::wait to execute the work, then call this function again with the same key to pick up the result.

Futures that complete immediately are not queued.

pub fn pending_count(&self) -> usize

Returns the number of pending futures.

pub fn wait(&mut self) -> bool

Run all pending futures. Returns true if there was no work to do.

Layout

Note: Unable to compute type layout, possibly due to this type having generic parameters. Layout can only be computed for concrete, fully-instantiated types.