export declare type DefaultOrFunc<T> = T | (() => T);
/** Get `T` in `DefaultOrFunc<T>` */
export declare function getDefault<T>(defv: DefaultOrFunc<T>): T;
/** Identity function */
export declare function identity<T>(val: T): T;
/** Guard value type */
export declare function guard<T>(val: T): T;
/** Do nothing */
export declare function empty(): void;
/** `throw 'todo'` */
export declare function TODO(reason?: any): never;
/** throw but expression */
export declare function raise(err: any): never;
/** Promise that will never continue */
export declare function abort(): Promise<never>;
/** Yield time slice */
export declare function Yield(): Promise<void>;
/** build tuple */
export declare function tuple<T extends unknown[]>(...vals: T): T;