javascript / intermediate
Snippet
Reactive Composition with Derived Stores
Derived stores allow you to create a store whose value depends on one or more other stores. Whenever the source stores change, the derived store recalculates its value efficiently.
snippet.js
javascript
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import { derived } from 'svelte/store';import { count } from './stores.js';export const doubled = derived(count,$count => $count * 2);
svelte
Breakdown
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import { derived } from 'svelte/store';
Imports the derived helper to create dependent reactive state.
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count,
The first argument is the input store (or an array of stores).
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$count => $count * 2
The callback receives the current values and returns the new derived value.