Trait StreamExt

pub trait StreamExt: Stream {
    // Provided method
    fn buffer_unordered_weighted<Fut>(
        self,
        max_weight: usize,
    ) -> BufferUnorderedWeighted<Self>
       where Self: Sized + Stream<Item = (usize, Fut)>,
             Fut: Future { ... }
}

An extension trait for Streams that provides buffer_unordered_weighted.

Provided Methods

fn buffer_unordered_weighted<Fut>( self, max_weight: usize, ) -> BufferUnorderedWeighted<Self>

where Self: Sized + Stream<Item = (usize, Fut)>, Fut: Future,

An adaptor for creating a buffered list of pending futures (unordered), where each future has a different weight.

This stream must return values of type (usize, impl Future), where the usize indicates the weight of each future. This adaptor will buffer futures up to weight max_weight, and then return the outputs in the order in which they complete.

The weight may be exceeded if the last future to be queued has a weight greater than max_weight minus the total weight of currently executing futures. However, no further futures will be queued until the total weights of running futures falls below max_weight.

The adaptor will schedule futures in the order they’re returned by the stream, without doing any reordering based on weight.

The weight of a future can be zero, in which case it will not count towards the total weight.

The returned stream will be a stream of each future’s output.

Examples

See the crate documentation for an example.

Implementors

impl<T> StreamExt for T

where T: Stream + ?Sized,