anchor.diff:    The alternative could implement a different strategy, extend the default class,
     or fake the behavior of the real class in a test case.
   
  -  We see two examples in the `HeroOfTheMonthComponent`:
  +  Here are two examples in the `HeroOfTheMonthComponent`:
   +makeExample('cb-dependency-injection/ts/src/app/hero-of-the-month.component.ts','use-class')(format='.')
   :marked
     The first provider is the *de-sugared*, expanded form of the most typical case in which the
     class to be created (`HeroService`) is also the provider's injection token.
  -  We wrote it in this long form to de-mystify the preferred short form.
  +  It's in this long form to de-mystify the preferred short form.
   
     The second provider substitutes the `DateLoggerService` for the `LoggerService`.
     The `LoggerService` is already registered at the `AppComponent` level.
  
positive.code:   another token that happens to have the same name.
  
    The `OpaqueToken` has these characteristics.
    We encountered them twice in the *Hero of the Month* example,
    in the *title* value provider and in the *runnersUp* factory provider.
  +makeExample('cb-dependency-injection/ts/src/app/hero-of-the-month.component.ts','provide-opaque-token')(format='.')
  :marked
    We created the `TITLE` token like this:
  +makeExample('cb-dependency-injection/ts/src/app/hero-of-the-month.component.ts','opaque-token')(format='.')
  
  
  
negative.code: +makeExample('cb-dependency-injection/ts/src/app/hero-bio.component.ts','component','src/app/hero-bio.component.ts')
  :marked
    The parent `HeroBiosComponent` binds a value to the `heroId`.
    The `ngOnInit` passes that `id` to the service, which fetches and caches the hero.
    The getter for the `hero` property pulls the cached hero from the service.
    And the template displays this data-bound property.
  
  