export declare function uniqBy(arr: T[], fn: (cur: T) => any): T[]; export declare function compact(a: (T | undefined)[]): T[]; export declare function castArray(input?: T | T[]): T[]; export declare function sortBy(arr: T[], fn: (i: T) => sort.Types | sort.Types[]): T[]; export declare namespace sort { type Types = string | number | undefined | boolean; } export declare function template(context: any): (t: string) => string;