export declare function map<T, R>(array: T[], callback: (item: T) => R): R[];
export declare function mapWithIndex<T, R>(array: T[], callback: (item: T, index: number) => R): R[];
export declare function filter<T>(array: T[], callback: (item: T) => boolean): T[];
export declare function filterWithIndex<T>(array: T[], callback: (item: T, index: number) => boolean): T[];
export declare function flatMap<T, R>(array: T[], callback: (item: T) => R[]): R[];