> [NOTE!] Svelte provides reactive implementations of built-in classes like `Set` and `Map` that can be imported from [`svelte/reactivity`](svelte-reactivity).
### Built-in classes
Svelte provides reactive implementations of built-in classes like `Set`, `Map`, `Date` and `URL` that can be imported from [`svelte/reactivity`](svelte-reactivity).
@ -254,39 +254,24 @@ To declare that a variable expects the constructor or instance type of a compone
Svelte provides a best effort of all the HTML DOM types that exist. Sometimes you may want to use experimental attributes or custom events coming from an action. In these cases, TypeScript will throw a type error, saying that it does not know these types. If it's a non-experimental standard attribute/event, this may very well be a missing typing from our [HTML typings](https://github.com/sveltejs/svelte/blob/main/packages/svelte/elements.d.ts). In that case, you are welcome to open an issue and/or a PR fixing it.
In case this is a custom or experimental attribute/event, you can enhance the typings like this:
// If you want to use the beforeinstallprompt event
onbeforeinstallprompt?: (event: any) => any;
// If you want to use myCustomAttribute={..} (note: all lowercase)
mycustomattribute?: any; // You can replace any with something more specific if you like
}
}
```
Then make sure that `d.ts` file is referenced in your `tsconfig.json`. If it reads something like `"include": ["src/**/*"]` and your `d.ts` file is inside `src`, it should work. You may need to reload for the changes to take effect.
You can also declare the typings by augmenting the `svelte/elements` module like this:
In case this is a custom or experimental attribute/event, you can enhance the typings by augmenting the `svelte/elements` module like this:
```ts
/// file: additional-svelte-typings.d.ts
import { HTMLButtonAttributes } from 'svelte/elements';
declare module 'svelte/elements' {
// add a new element
export interface SvelteHTMLElements {
'custom-button': HTMLButtonAttributes;
}
// allows for more granular control over what element to add the typings to
// add a new global attribute that is available on all html elements
export {}; // ensure this is not an ambient module, else types will be overridden instead of augmented
```
Then make sure that the `d.ts` file is referenced in your `tsconfig.json`. If it reads something like `"include": ["src/**/*"]` and your `d.ts` file is inside `src`, it should work. You may need to reload for the changes to take effect.
The same applies to array mutations, since these both read and write to the array:
```js
let array = $state([]);
let array = $state(['hello']);
$effect(() => {
array.push('hello');
array.push('goodbye');
});
```
@ -238,3 +238,23 @@ let odd = $derived(!even);
```
If side-effects are unavoidable, use [`$effect`]($effect) instead.
### svelte_boundary_reset_onerror
```
A `<svelte:boundary>``reset` function cannot be called while an error is still being handled
```
If a [`<svelte:boundary>`](https://svelte.dev/docs/svelte/svelte-boundary) has an `onerror` function, it must not call the provided `reset` function synchronously since the boundary is still in a broken state. Typically, `reset()` is called later, once the error has been resolved.
If it's possible to resolve the error inside the `onerror` callback, you must at least wait for the boundary to settle before calling `reset()`, for example using [`tick`](https://svelte.dev/docs/svelte/lifecycle-hooks#tick):
@ -312,6 +312,32 @@ Reactive `$state(...)` proxies and the values they proxy have different identiti
To resolve this, ensure you're comparing values where both values were created with `$state(...)`, or neither were. Note that `$state.raw(...)` will _not_ create a state proxy.
### svelte_boundary_reset_noop
```
A `<svelte:boundary>``reset` function only resets the boundary the first time it is called
```
When an error occurs while rendering the contents of a [`<svelte:boundary>`](https://svelte.dev/docs/svelte/svelte-boundary), the `onerror` handler is called with the error plus a `reset` function that attempts to re-render the contents.
This `reset` function should only be called once. After that, it has no effect — in a case like this, where a reference to `reset` is stored outside the boundary, clicking the button while `<Contents />` is rendered will _not_ cause the contents to be rendered again.
The same applies to array mutations, since these both read and write to the array:
```js
let array = $state([]);
let array = $state(['hello']);
$effect(() => {
array.push('hello');
array.push('goodbye');
});
```
@ -184,3 +184,21 @@ let odd = $derived(!even);
```
If side-effects are unavoidable, use [`$effect`]($effect) instead.
## svelte_boundary_reset_onerror
> A `<svelte:boundary>``reset` function cannot be called while an error is still being handled
If a [`<svelte:boundary>`](https://svelte.dev/docs/svelte/svelte-boundary) has an `onerror` function, it must not call the provided `reset` function synchronously since the boundary is still in a broken state. Typically, `reset()` is called later, once the error has been resolved.
If it's possible to resolve the error inside the `onerror` callback, you must at least wait for the boundary to settle before calling `reset()`, for example using [`tick`](https://svelte.dev/docs/svelte/lifecycle-hooks#tick):
@ -272,6 +272,30 @@ To silence the warning, ensure that `value`:
To resolve this, ensure you're comparing values where both values were created with `$state(...)`, or neither were. Note that `$state.raw(...)` will _not_ create a state proxy.
## svelte_boundary_reset_noop
> A `<svelte:boundary>``reset` function only resets the boundary the first time it is called
When an error occurs while rendering the contents of a [`<svelte:boundary>`](https://svelte.dev/docs/svelte/svelte-boundary), the `onerror` handler is called with the error plus a `reset` function that attempts to re-render the contents.
This `reset` function should only be called once. After that, it has no effect — in a case like this, where a reference to `reset` is stored outside the boundary, clicking the button while `<Contents />` is rendered will _not_ cause the contents to be rendered again.
```svelte
<script>
let reset;
</script>
<buttononclick={reset}>reset</button>
<svelte:boundaryonerror={(e,r)=> (reset = r)}>
<!-- contents -->
{#snippet failed(e)}
<p>oops! {e.message}</p>
{/snippet}
</svelte:boundary>
```
## transition_slide_display
> The `slide` transition does not work correctly for elements with `display: %value%`
consterror=newError(`svelte_boundary_reset_onerror\nA \`<svelte:boundary>\`\`reset\` function cannot be called while an error is still being handled\nhttps://svelte.dev/e/svelte_boundary_reset_onerror`);
console.warn(`%c[svelte] svelte_boundary_reset_noop\n%cA \`<svelte:boundary>\`\`reset\` function only resets the boundary the first time it is called\nhttps://svelte.dev/e/svelte_boundary_reset_noop`,bold,normal);
ComputerGuy
2 months ago