lib.rs:

将Result映射到Future的Result的惯用方式。

示例用法

use future_result::FutureResult;

async fn add_1(x: u32) -> u32 {
    x + 1
}

fn main() {
    let fut = async {
        let ok: Result<u32, ()> = Ok(41);
        let ok = ok.then_map(add_1).await;

        assert_eq!(Ok(42), ok);

        // ...

        let err: Result<(), u32> = Err(9);
        let err = err.then_map_err(add_1).await;

        assert_eq!(Err(10), err);
    };

    futures::executor::block_on(fut);
}