@ -130,6 +130,22 @@ Components can declare a generic relationship between their properties. One exam
The content of `generics` is what you would put between the `<...>` tags of a generic function. In other words, you can use multiple generics, `extends` and fallback types.
## Typing wrapper components
In case you're writing a component that wraps a native element, you may want to expose all the attributes of underlying element to the user. In that case, use (or extend from) one of the interfaces provided by `svelte/elements`. Here's an example for a `Button` component:
```svelte
<scriptlang="ts">
import type { HTMLButtonAttributes } from 'svelte/elements';
let { children, ...rest }: HTMLButtonAttributes = $props();
</script>
<button{...rest}>
{@render children()}
</button>
```
## Typing `$state`
You can type `$state` like any other variable.
@ -159,9 +175,9 @@ class Counter {
## The `Component` type
Svelte components or of type `Component`. You can use it and its related types to express a variety of constraints.
Svelte components are of type `Component`. You can use it and its related types to express a variety of constraints.
Using it together with `<svelte:component>` to restrict what kinds of component can be passed to it:
Using it together with dynamic components to restrict what kinds of component can be passed to it:
```svelte
<scriptlang="ts">
@ -170,13 +186,13 @@ Using it together with `<svelte:component>` to restrict what kinds of component
interface Props {
// only components that have at most the "prop"
// property required can be passed
component: Component<{ prop: string }>;
DynamicComponent: Component<{ prop: string }>;
}
let { component }: Props = $props();
let { DynamicComponent }: Props = $props();
</script>
<svelte:component this={component}prop="foo"/>
<DynamicComponentprop="foo"/>
```
Closely related to the `Component` type is the `ComponentProps` type which extracts the properties a component expects.