Expand description
Provides utilities for peeking at items in [futures::Stream
].
§Stability of peeked values
Implementors of this trait guarantee that a peeked Poll::Ready
result is
required to remain at the head of the stream until
[futures::Stream::poll_next
] or another method requiring a &mut
reference (and documented to potentially change the head of the stream) is
called. e.g. a caller holding a Pin<&mut Self>
that observes a Ready value
via PeekableStream::poll_peek
is guaranteed to observe that same value
again on a subsequent call to PeekableStream::poll_peek
,
[futures::Stream::poll_next
], etc.
This property must not be relied up on to prove soundness, but can be relied upon to prove correctness.
Traits§
- Peekable
Stream - A stream that provides the ability to peek at the next available item.
- Unobtrusive
Peekable Stream - A stream that supports peeking without perturbing any registered waker.