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svelte/documentation/docs/03-template-syntax/05-await.md

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---
title: {#await ...}
---
```svelte
<!--- copy: false --->
{#await expression}...{:then name}...{:catch name}...{/await}
```
```svelte
<!--- copy: false --->
{#await expression}...{:then name}...{/await}
```
```svelte
<!--- copy: false --->
{#await expression then name}...{/await}
```
```svelte
<!--- copy: false --->
{#await expression catch name}...{/await}
```
Await blocks allow you to branch on the three possible states of a [`Promise`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Promise) — pending, fulfilled or rejected.
```svelte
{#await promise}
<!-- promise is pending -->
<p>waiting for the promise to resolve...</p>
{:then value}
<!-- promise was fulfilled or not a Promise -->
<p>The value is {value}</p>
{:catch error}
<!-- promise was rejected -->
<p>Something went wrong: {error.message}</p>
{/await}
```
> [!NOTE] During server-side rendering, only the pending branch will be rendered.
>
> If the provided expression is not a `Promise` only the `:then` branch will be rendered, including during server-side rendering.
The `catch` block can be omitted if you don't need to render anything when the promise rejects (or no error is possible).
```svelte
{#await promise}
<!-- promise is pending -->
<p>waiting for the promise to resolve...</p>
{:then value}
<!-- promise was fulfilled -->
<p>The value is {value}</p>
{/await}
```
If you don't care about the pending state, you can also omit the initial block.
```svelte
{#await promise then value}
<p>The value is {value}</p>
{/await}
```
Similarly, if you only want to show the error state, you can omit the `then` block.
```svelte
{#await promise catch error}
<p>The error is {error}</p>
{/await}
```