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

# Function futures::future::err [−] [src]

    pub fn err<T, E>(e: E) -> FutureResult<T, E>

Creates a "leaf future" from an immediate value of a failed computation.

The returned future is similar to `result` where it will immediately run a scheduled callback with the provided value.

# Examples

    use futures::future::*;

    let future_of_err_1 = err::<u32, u32>(1);

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