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svelte/site/content/tutorial/14-composition/04-slot-props/text.md

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---
title: Slot props
---
In this app, we have a `<Hoverable>` component that tracks whether the mouse is currently over it. It needs to pass that data *back* to the parent component, so that we can update the slotted contents.
For this, we use *slot props*. In `Hoverable.svelte`, pass the `hovering` value into the slot:
```html
<div on:mouseenter={enter} on:mouseleave={leave}>
<slot hovering={hovering}></slot>
</div>
```
> Remember you can also use the `{hovering}` shorthand, if you prefer.
Then, to expose `hovering` to the contents of the `<Hoverable>` component, we use the `let` directive:
```html
<Hoverable let:hovering={hovering}>
<div class:active={hovering}>
{#if hovering}
<p>I am being hovered upon.</p>
{:else}
<p>Hover over me!</p>
{/if}
</div>
</Hoverable>
```
You can rename the variable, if you want — let's call it `active` in the parent component:
```html
<Hoverable let:hovering={active}>
<div class:active>
{#if active}
<p>I am being hovered upon.</p>
{:else}
<p>Hover over me!</p>
{/if}
</div>
</Hoverable>
```
You can have as many of these components you like, and the slotted props will remain local to the component where they're declared.
> Named slots can also have props; use the `let` directive on an element with a `slot="..."` attribute, instead of on the component itself.