export type DefinedValue<T> = {
    readonly isDefined: true;
    readonly value: T;
};
export type UndefinedValue = {
    readonly isDefined: false;
};
export type Maybe<T> = DefinedValue<T> | UndefinedValue;
export declare function definedValue<T>(value: T): DefinedValue<T>;
export declare function undefinedValue(): UndefinedValue;
export declare function map<T, U>(maybe: Maybe<T>, map: (value: T) => U): Maybe<U>;
export declare function resolve<T>(maybe: Maybe<T>): T | undefined;