Trait AsyncMapExt 

pub trait AsyncMapExt<T> {
    // Required methods
    fn async_map<TFn, TFuture>(self, f: TFn) -> AsyncMap<T, TFn, TFuture>
       where TFn: FnOnce(T) -> TFuture,
             TFuture: Future;
    fn async_and_then<U, TFn, TFuture>(
        self,
        f: TFn,
    ) -> AsyncAndThen<T, TFn, TFuture>
       where TFn: FnOnce(T) -> TFuture,
             TFuture: Future<Output = Option<U>>;
}

Required Methods

fn async_map<TFn, TFuture>(self, f: TFn) -> AsyncMap<T, TFn, TFuture>

where TFn: FnOnce(T) -> TFuture, TFuture: Future,

Basically same as Option::map, but it accepts closure that returns Future

Examples

use async_hofs::prelude::*;

assert_eq!(
    Some(1).async_map(|x: i32| async move { x + 1 }).await,
    Some(2),
);

assert_eq!(
    None.async_map(|x: i32| async move { x + 1 }).await,
    None
);

fn async_and_then<U, TFn, TFuture>( self, f: TFn, ) -> AsyncAndThen<T, TFn, TFuture>

where TFn: FnOnce(T) -> TFuture, TFuture: Future<Output = Option<U>>,

Basically same as Option::and_then, but it accepts closure that returns Future

Examples

use async_hofs::prelude::*;

assert_eq!(
    Some(1)
        .async_and_then(|x: i32| async move { Some(x + 1) })
        .await,
    Some(2),
);

assert_eq!(
    Some(1)
        .async_and_then(|x: i32| async move { Option::<i32>::None })
        .await,
    None
);

assert_eq!(
    None.async_and_then(|x: i32| async move { Some(x + 1) })
        .await,
    None
);

Dyn Compatibility

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety", so this trait is not object safe.

Implementations on Foreign Types

impl<T> AsyncMapExt<T> for Option<T>

fn async_map<TFn, TFuture>(self, f: TFn) -> AsyncMap<T, TFn, TFuture>

where TFn: FnOnce(T) -> TFuture, TFuture: Future,

fn async_and_then<U, TFn, TFuture>( self, f: TFn, ) -> AsyncAndThen<T, TFn, TFuture>

where TFn: FnOnce(T) -> TFuture, TFuture: Future<Output = Option<U>>,

Implementors