/**
 * An Option represents a collection of size 0 or 1.  Traditionally it's used as a replacement for
 * `null` or `undefined` to explicitly encode if a value can be empty or not.
 *
 * :TODO: Narrow self-type in `getOrElse` and `orElse` interfaces.
 */
interface Option<A> {
    isDefined: boolean;
    isEmpty: boolean;
    equals<B>(other: Option<B>): boolean;
    filter(predicate: (value: A) => boolean): Option<A>;
    filterNot(predicate: (value: A) => boolean): Option<A>;
    flatMap<B>(flatMapper: (value: A) => Option<B>): Option<B>;
    foreach(run: (value: A) => void): void;
    get(): A;
    getOrElse<B>(defaultValue: () => B): B;
    map<B>(mapper: (value: A) => B): Option<B>;
    match<B>(matcher: {
        Some: (a: A) => B;
        None: () => B;
    }): B;
    orElse<B>(alternative: () => Option<B>): Option<B>;
}
declare function Option<A>(value: A | null | undefined): Option<A>;
declare namespace Option {
    /**
     * This error is thrown when `None.get()` is called.
     */
    class NoSuchElementError extends Error {
        constructor();
    }
    function flatten<A>(options: Array<Option<A>>): Array<A>;
}
export { Option };