svelte/documentation/docs/98-reference/.generated/shared-errors.md

invalid_default_snippet

Cannot use `{@render children(...)}` if the parent component uses `let:` directives. Consider using a named snippet instead

This error would be thrown in a setup like this:

<!--- file: Parent.svelte --->
<List {items} let:entry>
    <span>{entry}</span>
</List>

<!--- file: List.svelte --->
<script>
    let { items, children } = $props();
</script>

<ul>
    {#each items as item}
        <li>{@render children(item)}</li>
    {/each}
</ul>

Here, List.svelte is using {@render children(item) which means it expects Parent.svelte to use snippets. Instead, Parent.svelte uses the deprecated let: directive. This combination of APIs is incompatible, hence the error.

lifecycle_outside_component

`%name%(...)` can only be used during component initialisation

Certain lifecycle methods can only be used during component initialisation. To fix this, make sure you're invoking the method inside the top level of the instance script of your component.

<script>
    import { onMount } from 'svelte';

    function handleClick() {
        // This is wrong
        onMount(() => {})
    }

    // This is correct
    onMount(() => {})
</script>

<button onclick={handleClick}>click me</button>

store_invalid_shape

`%name%` is not a store with a `subscribe` method

svelte_element_invalid_this_value

The `this` prop on `<svelte:element>` must be a string, if defined