Creating a service to manage feed menu

Well, now we can fetch RSS feeds. But the plan was to have a manageable menu of feeds. I think, we can represent the menu in an array of items, where each item can be described with the following interface:

./app/ts/Interfaces/index.ts

export interface IMenuItem { 
  url: string; 
  title: string; 
  id: string; 
} 

As for the service itself, let's also start with the interface:

./app/ts/Services/IMenu.ts

import { IMenuItem } from "../Interfaces"; 
 
export interface IMenu { 
  items: IMenuItem[]; 
  clear(): void; 
  remove( url: string ): IMenuItem[]; 
  add( url: string, title: string ): IMenuItem[]; 
  load(): IMenuItem[]; 
} 

To some degree, it's like Test-Driven development. We describe the contents of the class without implementation to get the whole picture. Then, we populate the members one by one:

./app/ts...