title: switchMap is not a function
body: <p>I have followed tutorial Angular Tour of Heroes and some other, now I'm trying to build apps with Angular 2. Basically when we're listening to change with Subject, we can wait for some seconds so that request won't burden the network.</p>
  
  <p>Here is my code :</p>
  
  <pre><code>import { Injectable } from '@angular/core';
  import {Http} from "@angular/http";
  import {Observable} from "rxjs/Observable";
  import 'rxjs/add/observable/of';
  import 'rxjs/add/operator/catch';
  import 'rxjs/add/operator/debounceTime';
  import 'rxjs/add/operator/distinctUntilChanged';
  import 'rxjs/add/operator/switchMap';
  import {Employee} from "../employee";
  
  @Injectable()
  export class EmployeeSearchService {
  
    private getPersonalURL:string = 'api/employee';   // I'm using mock, btw
  
    constructor(private http:Http) { }
  
    search(term:string): Observable&lt;Employee[]&gt; {
      return this.http.get(`api/employee/?firstName=${term}`)
        .map(response =&gt;  response.json().data as Employee[])
        .catch(this.handleError);
    }
  
    searchEmployees(term: Observable&lt;string&gt;): Observable&lt;Employee[]&gt; {
      return term.debounceTime(200)
         .distinctUntilChanged()
         .switchMap(term =&gt; this.search(term)); // here is the error
    }
  
    private handleError(error: any): Promise&lt;any&gt; {
      console.error('Error on EmployeeSearchService', error);
      return Promise.reject(error.message || error);
    }
  
  }
  </code></pre>
  
  <p>And this is the calling component :</p>
  
  <pre><code>import { Component, OnInit } from '@angular/core';
  import {Subject} from "rxjs/Subject";
  import { EmployeeService } from '../employee.service';
  import { Employee } from '../employee'
  import {EmployeeSharedService} from "../employee-shared.service";
  import {EmployeeSearchService} from "../employee-search/employee-search.service";
  
  @Component({
    selector: 'employee-list',
    providers: [ EmployeeService ],
    templateUrl: './employee-list.component.html',
    styleUrls: ['./employee-list.component.css']
  })
  export class EmployeeListComponent implements OnInit {
  
    employees: Employee[];
    selectedEmployee: Employee;
    sortAsc: boolean;
  
    searchQuery = new Subject&lt;string&gt;();
  
    constructor(private employeeService:EmployeeService, private employeeSearchService:EmployeeSearchService, private employeeSharedService:EmployeeSharedService) {
      this.sortAsc = true;
  
    }
  
    ngOnInit() {    // called from here
      this.employeeSearchService.searchEmployees(this.searchQuery)
          .subscribe(result =&gt; {
            this.employees = result;
            if(!result) {
              this.getAllEmployees();
            }
          });
    }
  
    getAllEmployees(): void {
        // calling get all in service
    }
  
  }
  </code></pre>
  
  <p>There are error that says </p>
  
  <pre><code>TypeError: term.debounceTime(...).distinctUntilChanged(...).switchMap is not a function
  </code></pre>
  
  <p>Am I missing something, like import or other thing? Because exact code and import are same as Angular Tour of Heroes tutorial, and mine works. But this one isn't.</p>