export type Dual<T> = T & PromiseLike<T>;
export declare const DUAL_PENDING: unique symbol;
export declare const throwDualPending: () => never;
export type AsyncMethodKeys<T> = {
    [K in keyof T]-?: T[K] extends (...args: any[]) => Promise<any> ? K : never;
}[keyof T];
export interface DualizeOptions<T> {
    /** 这些方法在 undecided/pending 时会返回延迟执行函数，等待对象 Promise 完成后再调用 */
    asyncMethods?: readonly (keyof T)[];
}
export declare function dualizeAny<T>(sync: () => T, // 同步构造；若抛错则视为 rejected
asyncFn: () => Promise<T>, // 异步构造
options?: DualizeOptions<T>): Dual<T>;