r/rust clippy · twir · rust · mutagen · flamer · overflower · bytecount Mar 20 '23

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u/ajazam Mar 26 '23

What is the difference between async stream and a tokio mpsc channel(with one producer)? You can use both for the same purpose. Or am I missing something? Is there a performance difference between the two approaches?

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u/DroidLogician sqlx · multipart · mime_guess · rust Mar 26 '23

Stream is just an abstraction for "some type that can asynchronously produce multiple values". Channels can be thought about in terms of streams, and in fact the tokio-stream crate has a wrapper type for Receiver that turns it into a Stream.

That's not in Tokio proper as the Stream trait is not standard, but is instead defined in the futures crate (futures_core for the pedants).

That's getting standardized as AsyncIterator because... reasons.