Spring Class — svelte Architecture

Source Code

packages/svelte/src/motion/public.d.ts lines 39–81

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;
}