declare enum tag {
    'right' = "right",
    'left' = "left"
}
export interface ILeft<A> {
    value: A;
    tag: tag.left;
}
export interface IRight<B> {
    value: B;
    tag: tag.right;
}
export declare type Either<A, B> = ILeft<A> | IRight<B>;
export declare type Maybe<T> = Either<Error, T>;
export declare const Left: <A>(val: A) => ILeft<A>;
export declare const Right: <B>(val: B) => IRight<B>;
export declare const isLeft: <A, B>(val: Either<A, B>) => val is ILeft<A>;
export declare const isRight: <A, B>(val: Either<A, B>) => val is IRight<B>;
export declare const either: <L, R, A, B>(leftFn: (left: L) => A, rightFn: (right: R) => B, value: Either<L, R>) => A | B;
export declare const whenRight: <L, R, T>(resolve: (value: R) => T | Promise<T>) => (value: Either<L, R> | Promise<Either<L, R>>) => Promise<T | ILeft<L>>;
export declare const tryCatch: <T>(fn: () => Promise<T>) => Promise<Maybe<T>>;
export {};