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explore / Web & frontend / mozg / Svelte 5 & SvelteKit

Svelte · Language

Answer questions about the Svelte 5 language exactly as specified: each rune ($state, $derived, $effect, $props, $bindable and the rest) with its precise semantics, snippets and render tags, event attributes, component lifecycle, stores, and what replaced every Svelte 4 pattern.

1109 notes · updated 2026-08-04 · trained 75%

Ask it things like

answers 21/29 on its latest exam
How do you make a prop two-way bindable in Svelte 5?Core Runes: $bindable✓
How do you create derived reactive values in Svelte 5?Core Runes: $derived✓
What is the purpose of the $effect rune?Core Runes: $effect✓
How do you declare reactive state in Svelte 5 runes mode?Core Runes: $state✓
What is the syntax for event attributes in Svelte 5?Event Attributes✓
What replaces reactive let/var declarations from Svelte 4?Migration Patterns✓
What replaces export let props from Svelte 4?Migration Patterns✓
What is a snippet in Svelte 5?Snippets & Render Tags✓
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What it can answer

29 checks
75%
✓Core Runes: $state3 / 3
✓Event Attributes3 / 3
▲Migration Patterns3 / 5
▲Snippets & Render Tags3 / 4
✓Core Runes: $bindable2 / 2
▲Core Runes: $derived2 / 3
▲Core Runes: $effect2 / 3
▲Component Lifecycle1 / 2
▲Core Runes: $props1 / 2
▲Stores1 / 2
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Inside

  • Legacy prop default values behavior in undefined case · core/legacy
  • Suppressing required prop warnings in legacy mode · core/legacy
  • Exported const, class, and function declarations in legacy components · core/legacy
  • Legacy export let syntax for component props · core/legacy
  • Renaming props in legacy mode with separate export keyword · core/legacy
  • $: server-side rendering behavior · core/legacy
  • $: topological ordering with indirect dependencies pitfall · core/legacy
  • $: topological ordering of statements · core/legacy
  • $: dependency detection at compile time · core/legacy
  • $: multiple statements in a block · core/legacy
  • $: reactive statements legacy mode overview · core/legacy
  • $: destructuring assignment in reactive statements · core/legacy
  • $: reactive assignment example · core/legacy
  • $: indirect dependency pitfall · core/legacy

Licence

CC BY-NC-SA 4.0

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