declare global {
    interface Generator<T = unknown, TReturn = any, TNext = unknown> {
        /**
         * Concatenates two sequences.
         * @param item The sequence to concatenate to the first sequence.
         * @returns A Generator<T> that contains the concatenated elements of the two input sequences.
         */
        concat(item: Generator<T, TNext, TReturn> | T[]): Generator<T, TNext, TReturn>;
    }
    interface AsyncGenerator<T = unknown, TReturn = any, TNext = unknown> {
        /**
         * Concatenates two sequences.
         * @param item The sequence to concatenate to the first sequence.
         * @returns An AsyncGenerator<T> that contains the concatenated elements of the two input sequences.
         */
        concat(item: AsyncGenerator<T, TNext, TReturn> | Generator<T, TNext, TReturn> | T[]): AsyncGenerator<T, TNext, TReturn>;
    }
}
export {};