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menu_book Course Curriculum (Svelte 5) expand_more

Component Syntax

SFC anatomy Markup expressions If blocks Each blocks Await blocks Class directives Style directives Event handlers

Runes & Reactivity

$state $derived $effect $props $bindable Reactive collections State ownership Deep reactivity

Composition

Props Callback props Bindings Snippets {@render} Context Actions DOM references

Motion & Lifecycle

Mounting tick Transitions Custom transitions Animations Crossfade Motion preferences Browser-only code

SvelteKit Routing

File-based routes Layouts Load functions Form actions Server routes Error pages Cookies Environment modules

Production

Server-only modules Validation SSR and hydration Prerendering Adapters Testing Performance budgets Deployment architecture

Svelte 5 / Runes & Reactivity

$effect

Learn $effect in Svelte 5 with a dedicated explanation, a concept-specific example, a production caution, and a mastery check.

12 min read • Beginner

svelte-5-011.svelte

svelte

<script>let room=$state("general");$effect(()=>{console.log("connect",room);return()=>console.log("disconnect",room)});</script>

What to watch

Content source & attribution

Original Syntaxis Content · Original Syntaxis Content

Lesson quizzes

$effect Mastery Check →