> For the complete documentation index, see [llms.txt](https://docs.corets.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.corets.io/observables/async.md).

# Async

Source code is hosted in [GitHub](https://github.com/corets/async)

{% tabs %}
{% tab title="yarn" %}

```bash
yarn add @corets/async
```

{% endtab %}

{% tab title="npm" %}

```
npm install --save @corets/async
```

{% endtab %}
{% endtabs %}

Seamless React integrations are shipped inside separate packages:

{% content-ref url="/pages/-MfJ4qThZ0llSH30K7PI" %}
[useAsync](/hooks/use-async.md)
{% endcontent-ref %}

{% content-ref url="/pages/-MeeFDXYVzHIrXuHDnFE" %}
[useStream](/hooks/use-stream.md)
{% endcontent-ref %}

{% content-ref url="/pages/-MeeFDVtWtL6cM6Te5\_Y" %}
[useAction](/hooks/use-action.md)
{% endcontent-ref %}

## createAsync()

Create an observable async operation:

```typescript
import { createAsync } from "@corets/async"

const query = createAsync(async () => "some data")
```

Create an observable async operation without the factory function:

```typescript
import { Async } from "@corets/async"

const query = new Async(async () => "some data")
```

## Async.getResult()

Retrieve result from the last invocation:

```typescript
query.getResult()
```

## Async.getError()

Retrieve probable error from the last invocation:

```typescript
query.getError()
```

## Async.getState()

Retrieve all the details in a single call, contains values like `isRunning`, `isCancelled`, `result`, etc.:

```typescript
query.getState()
```

## Async.isRunning()

Check if the async operation is being executed right now:

```typescript
query.isRunning()
```

## Async.isCancelled()

Check if the latest async invocation has been cancelled:

```typescript
query.isCancelled()
```

## Async.isErrored()

Check if the latest async invocation errored:

```typescript
query.isErrored()
```

## Async.run()

Invoke async operation:

```typescript
import { createAsync } from "@corets/async"

const query = createAsync(async (argument: number) => "some data")
const queryWithArguments = createAsync(async (argument: number) => `The value is ${argument}`)

const result = await query.run()
const anotherResult = await queryWithArguments.run(1337)
```

## Async.resolve()

Manually resolve async result, makes it available on the instance using [`getResult()`](/observables/async.md#async-getresult):

```typescript
import { createAsync } from "@corets/async"

const query = createAsync(async (argument: number) => "some data")

const resultFromValue = await query.resolve("another value")
const resultFromPromise = await query.resolve(Promise.resolve("another value"))
const resultFromProducer = await query.resolve(async () => "another value")
```

## Async.cancel()

Cancel current async invocation:

```typescript
query.cancel()
```

## Async.listen()

Subscribe to state changes, the listener receives the same object that you get from [`getState()`](/observables/async.md#async-getstate):

```typescript
const unsubscribe = query.listen((state) => console.log("async state changed", state))
```