Spring Class — svelte Architecture

Source Code

packages/svelte/types/index.d.ts lines 2024–2066

	export class Spring<T> {
		constructor(value: T, options?: SpringOpts);

		/**
		 * Create a spring whose value is bound to the return value of `fn`. This must be called
		 * inside an effect root (for example, during component initialisation).
		 *
		 * ```svelte
		 * <script>
		 * 	import { Spring } from 'svelte/motion';
		 *
		 * 	let { number } = $props();
		 *
		 * 	const spring = Spring.of(() => number);
		 * </script>
		 * ```
		 */
		static of<U>(fn: () => U, options?: SpringOpts): Spring<U>;

		/**
		 * Sets `spring.target` to `value` and returns a `Promise` that resolves if and when `spring.current` catches up to it.
		 *
		 * If `options.instant` is `true`, `spring.current` immediately matches `spring.target`.
		 *
		 * If `options.preserveMomentum` is provided, the spring will continue on its current trajectory for
		 * the specified number of milliseconds. This is useful for things like 'fling' gestures.
		 */
		set(value: T, options?: SpringUpdateOpts): Promise<void>;

		damping: number;
		precision: number;
		stiffness: number;
		/**
		 * The end value of the spring.
		 * This property only exists on the `Spring` class, not the legacy `spring` store.
		 */
		target: T;
		/**
		 * The current value of the spring.
		 * This property only exists on the `Spring` class, not the legacy `spring` store.
		 */
		get current(): T;
	}