Struct JsFuture 

pub struct JsFuture<T = JsValue, E = JsValue> { /* private fields */ }

A Rust Future backed by a JavaScript Promise.

This type is constructed with a JavaScript Promise object and translates it to a Rust Future. This type implements the Future trait from the futures crate and will either succeed or fail depending on what happens with the JavaScript Promise.

A JsFuture<T, E> built from a Promise<T, E> resolves to Result<T, E>: the fulfilled value is converted as a T and the rejection reason as an E, both unchecked, just as JS could have settled the promise with anything.

Currently this type is constructed with JsFuture::from.

Trait Implementations

impl<T, E> Debug for JsFuture<T, E>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<T, E> ErasableGeneric for JsFuture<T, E>

type Repr = JsFuture

The singular concrete type that all generic variants can be transmuted on.

impl<T: FromWasmAbi + 'static, E: FromWasmAbi + 'static> From<Promise<T, E>> for JsFuture<T, E>

fn from(js: Promise<T, E>) -> JsFuture<T, E>

Converts to this type from the input type.

impl<T, E> Future for JsFuture<T, E>

type Output = Result<T, E>

The type of value produced on completion.

fn poll(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output>

Attempts to resolve the future to a final value, registering the current task for wakeup if the value is not yet available.

impl<T: UnwindSafe, E: UnwindSafe> UnwindSafe for JsFuture<T, E>

impl<T, E, Target, ErrTarget> Upcast<JsFuture<Target, ErrTarget>> for JsFuture<T, E>

where T: Upcast<Target>, E: Upcast<ErrTarget>,

fn upcast(&self) -> &T

where Self: ErasableGeneric, T: Sized + ErasableGeneric<Repr = Self::Repr>,

Perform a zero-cost type-safe upcast to a wider ref type within the Wasm bindgen generics type system.

fn upcast_into(self) -> T

where Self: Sized + ErasableGeneric, T: Sized + ErasableGeneric<Repr = Self::Repr>,

Perform a zero-cost type-safe upcast to a wider type within the Wasm bindgen generics type system.