title: How to inject different instances of a service based on scope
body: <p>I have created a directive with isolated scope, and I would like all items in that scope to get a particular implementation of a service when they get it injected. There are a couple ways I think I can accomplish the <em>equivalent</em>, but would like to know if there is a better approach:</p>
  
  <ul>
  <li>Not use injection at all, and instead assign the particular implementation of the service I want to $scope.myService, and have items access that member to get the service</li>
  <li><p>Have items pass $scope to the service's methods, which will vary their behavior based on what's in $scope</p>
  
  <p>I'm leaning towards the first option. But is seems that angular has the ability to inject different items based on $scope, since it does that when injecting $scope itself, and I'm wondering if I could use that mechanism somehow.</p></li>
  </ul>