anchor.diff:    ### 回顾应用结构
     Let’s verify that we have the following structure after all of our good refactoring in this chapter:
   
  -  来验证下吧，在本章中，经过这些漂亮的重构，我们应该得到下列结构：
  +  来验证下吧，在本章中，经过这些漂亮的重构，我们应该得到了下列结构：
     
   .filetree
     .file angular2-tour-of-heroes
  
positive.code: :marked
    Here are the code files we discussed in this chapter.
    
    这就是我们在本章讨论过的这些源码文件：
  
  +makeTabs(`
    toh-3/ts/app/hero-detail.component.ts,
  
negative.code:   ### *directives* 数组
    A browser ignores HTML tags and attributes that it doesn't recognize. So does Angular.
    
    浏览器会忽略它不认识的HTML标签和属性。Angular也是如此。
    
    We've imported `HeroDetailComponent`, we've used it in the template, but we haven't told Angular about it.
    
    我们引入了`HeroDetailComponent`，并在模板中使用它，但还没有告诉Angular。
    
    We tell Angular about it by listing it in the metadata `directives` array. Let's add that array property to the bottom of the
    `@Component` configuration object, immediately after the `template` and `styles` properties.
    
    我们要把它列在元数据的`directives`数组中，这样Angular才会知道它。
    让我们把这个数组属性加在`@Component`配置对象的底部，紧跟在`template`和`styles`属性之后。
    
  +makeExample('toh-3/ts/app/app.component.ts', 'directives')
  
  