Module queue 

The explicit thread boundary, and with it the error boundary.

A pipeline is synchronous until a Queue is placed in it. A Queue owns a worker thread and a bounded channel, so upstream and downstream of it run concurrently and a full channel becomes backpressure.

Crossing it changes how failure is handled. A direct Sink::consume call can return Err to its caller; a Queue’s worker has no caller to return to, so a downstream data error is posted to the Bus, that buffer is dropped, and the worker continues. OverflowPolicy decides what a full channel does, and its own documentation explains why an unbounded wait is the default and when it is the wrong one.

Structs

Queue

An explicit thread boundary.

Enums

OverflowPolicy

What a Queue does when its channel is full.

QueueError

Errors specific to Queue. Converts into the crate-wide Error via ? (see crate::error::Error).