/**
 * Computes the partial difference between two values.
 * Returns `undefined` if the values are equal, or `{ diff }` containing only the changed parts.
 * For arrays, the diff contains only items in `next` that have no deep-equal counterpart in `prev`.
 * For objects, the diff contains only keys whose values changed.
 *
 * @param prev - The original value
 * @param next - The updated value
 * @returns An object containing the diff, or `undefined` if the values are equal
 */
export declare function partialDiff<T>(prev: T, next: T): {
    diff: Partial<T>;
} | undefined;
/**
 * Deeply merges multiple values together. Objects are merged key-by-key recursively.
 * Arrays are merged by appending items that are not already present (by deep equality).
 * Primitives are resolved by taking the last argument.
 *
 * @param args - The values to merge, applied left to right
 * @returns The merged result
 */
export declare function deepMerge(...args: unknown[]): unknown;