title: Background task in Typescript
body: <p>I'm new in Angular 2 and typescript and used to do this in Java or Golang : </p>
  
  <p>I have a service with a stack and a routine that make a background (asynchronous) task only one time, on each element of this stack...</p>
  
  <p>I don't want to know who is pushing something in my stack and how it does, but I need to process each element in an inconspicuous asynchronous task.</p>
  
  <p><em>Edit : the task is a request and I want to group all the stack's elements in an array</em></p>
  
  <p>If I use Javascript interval to check my stack, I finally obtains some lags regardless of frequency.</p>
  
  <p>I know there is no thread notion in Typescript, but maybe a kind of best practice for background tasks ?</p>