# futures::stream::once - Rust
API documentation for the Rust `once` fn in crate `futures`.
Keywords: rust, rustlang, rust-lang, once

# Function futures::stream::once [−] [src]

    pub fn once<T, E>(item: Result<T, E>) -> Once<T, E>

Creates a stream of single element

    use futures::*;

    let mut stream = stream::once::<(), _>(Err(17));
    assert_eq!(Err(17), stream.poll());
    assert_eq!(Ok(Async::Ready(None)), stream.poll());

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