Trait AsyncOptionExt 

pub trait AsyncOptionExt<T> {
    // Required method
    async fn async_map<U, Fut: Future<Output = U>, F: FnOnce(T) -> Fut>(
        self,
        f: F,
    ) -> Option<U>;
}

Required Methods

async fn async_map<U, Fut: Future<Output = U>, F: FnOnce(T) -> Fut>( self, f: F, ) -> Option<U>

Maps an Option<T> to Option<U> by applying a function to a contained value (if Some) or returns None (if None).

Example

use composable_utils::AsyncOptionExt;

async fn double(x: usize) -> usize {
    x * 2
}

async_io::block_on(async {
    let value = Some(69);
    let value = value
        .async_map(|v| async move { double(v).await })
        .await
        .unwrap_or_else(|| panic!("value should always be Some"));
    assert_eq!(value, 138);
});

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> AsyncOptionExt<T> for Option<T>

async fn async_map<U, Fut: Future<Output = U>, F: FnOnce(T) -> Fut>( self, f: F, ) -> Option<U>

Implementors