svelte/documentation/docs/99-legacy/20-legacy-slots.md

title
<slot>

<slot><!-- optional fallback --></slot>

<slot name="x"><!-- optional fallback --></slot>

<slot prop={value} />

Components can have child content, in the same way that elements can.

The content is exposed in the child component using the <slot> element, which can contain fallback content that is rendered if no children are provided.

<!-- Widget.svelte -->
<div>
	<slot>
		this fallback content will be rendered when no content is provided, like in the first example
	</slot>
</div>

<!-- App.svelte -->
<Widget />
<!-- this component will render the default content -->

<Widget>
	<p>this is some child content that will overwrite the default slot content</p>
</Widget>

Note: If you want to render regular <slot> element, You can use <svelte:element this="slot" />.

[!NOTE] In Svelte 5+, use snippets instead

<slot name="name">

Named slots allow consumers to target specific areas. They can also have fallback content.

<!-- Widget.svelte -->
<div>
	<slot name="header">No header was provided</slot>
	<p>Some content between header and footer</p>
	<slot name="footer" />
</div>

<!-- App.svelte -->
<Widget>
	<h1 slot="header">Hello</h1>
	<p slot="footer">Copyright (c) 2019 Svelte Industries</p>
</Widget>

Components can be placed in a named slot using the syntax <Component slot="name" />. In order to place content in a slot without using a wrapper element, you can use the special element <svelte:fragment>.

<!-- Widget.svelte -->
<div>
	<slot name="header">No header was provided</slot>
	<p>Some content between header and footer</p>
	<slot name="footer" />
</div>

<!-- App.svelte -->
<Widget>
	<HeaderComponent slot="header" />
	<svelte:fragment slot="footer">
		<p>All rights reserved.</p>
		<p>Copyright (c) 2019 Svelte Industries</p>
	</svelte:fragment>
</Widget>

<slot key={value}>

Slots can be rendered zero or more times and can pass values back to the parent using props. The parent exposes the values to the slot template using the let: directive.

The usual shorthand rules apply — let:item is equivalent to let:item={item}, and <slot {item}> is equivalent to <slot item={item}>.

<!-- FancyList.svelte -->
<ul>
	{#each items as item}
		<li class="fancy">
			<slot prop={item} />
		</li>
	{/each}
</ul>

<!-- App.svelte -->
<FancyList {items} let:prop={thing}>
	<div>{thing.text}</div>
</FancyList>

Named slots can also expose values. The let: directive goes on the element with the slot attribute.

<!-- FancyList.svelte -->
<ul>
	{#each items as item}
		<li class="fancy">
			<slot name="item" {item} />
		</li>
	{/each}
</ul>

<slot name="footer" />

<!-- App.svelte -->
<FancyList {items}>
	<div slot="item" let:item>{item.text}</div>
	<p slot="footer">Copyright (c) 2019 Svelte Industries</p>
</FancyList>