export type DataType<T> = { key: string|number value: T}
export type NodeType = { data: DataType<any> next: null|NodeType}|null
export interface LinkedListApi { size: number; prepend(data: DataType<any>): boolean; append(data: DataType<any>): boolean; add(data: DataType<any>, position: number): boolean; getFromHead(): object|false; getFromTail(): object|false; log(): void; remove(key: string|number): boolean; update(key: string|number, newValue: any): object|boolean; search(key: string|number): object|boolean iterator(): Generator}