/**
 * 🎯 Decorator that ensures only a single in-flight invocation per argument list.
 * Subsequent calls with the same arguments return the same Promise until it settles.
 *
 * Usage:
 * ```typescript
 * class Example {
 *   @singleflight async fetchData(id: string): Promise<Data> { ... }
 * }
 *
 * const e = new Example();
 * const p1 = e.fetchData('foo');
 * const p2 = e.fetchData('foo'); // returns same Promise as p1
 * ```
 */
export declare function singleflight<A extends Array<unknown>, R extends Promise<unknown>>(value: unknown, context: ClassMethodDecoratorContext<object, (...args: A) => R>): (...args: A) => R;
export declare function singleflight<A extends Array<unknown>, R extends Promise<unknown>>(value: unknown, context: ClassFieldDecoratorContext<object, (...args: A) => R>): (originalFn: (...args: A) => R) => (...args: A) => R;