title: Inject nestjs service from another module
body: <p>I've got a <code>PlayersModule</code> and an <code>ItemsModule</code>.</p>
  
  <p>I want to use the <code>ItemsService</code> in the <code>PlayersService</code>.</p>
  
  <p>When I add it by injection:</p>
  
  <pre><code>import { Injectable } from '@nestjs/common';
  import { InjectModel } from 'nestjs-typegoose';
  import { ModelType, Ref } from 'typegoose';
  import { Player } from './player.model';
  import { Item } from '../items/item.model';
  import { ItemsService } from '../items/items.service';
  
  @Injectable()
  export class PlayersService {
      constructor(
          @InjectModel(Player) private readonly playerModel: ModelType&lt;Player&gt;,
          private readonly itemsService: ItemsService){}
  </code></pre>
  
  <p>I get this nest error :</p>
  
  <blockquote>
    <p>[Nest] 11592   - 2018-8-13 11:42:17   [ExceptionHandler] Nest can't
    resolve dependencies of the PlayersService (+, ?). Please make sure
    that the argument at index [1] is available in the current context.</p>
  </blockquote>
  
  <p>Both modules are imported in the <code>app.module.ts</code>. Both services are working alone in their module.</p>