title: How to properly chain rxjs 6 observables?
body: <p>Any suggestions, how this can be rewritten in more promise-chaining style?:</p>
  
  <pre><code>this.apiService.sendPutRequest('/api/users/activate', usrObj).pipe(
          map(() =&gt; {
              return this.apiService.sendGetRequest('/api/users/' + this.currentUserId).pipe(
                  map(data =&gt; {
                      return this.setActiveUser(data).pipe(
                          map(() =&gt; {
                              return this.apiService.sendGetRequest('api/tasks/user/' + this.currentUserId).pipe(
                                  map(tasks =&gt; {
                                      return this.taskService.setCurrentUserTasks(tasks);
                                  })
                              );
                          })
                      );
                  })
              );
          })
      );
  </code></pre>