title: Angular js - services and circular injection error
body: <p>Why does i can't inject services like this?</p>
  
  <pre><code>service('actionService',function (sessionService) {
   this.doAction = function () {
    return 5;
   }
  });
  service('sessionService',function (userService) {
   this.get = function {
      if(userService.check()){
      //do other stuffs 
      }
    }
  
  });
  service('userService',function (actionService) {
    this.check = function () {
    actionService.doAction();
    if(x = 9){ 
      return true;
    }else{ 
     return false; 
    } 
    }
  });
  </code></pre>
  
  <p>I get <code>"Circular injection error"</code> in console</p>
  
  <p>how to handle this now ?</p>
  
  <p>here a better code : <a href="http://pastebin.com/wS32UNCq" rel="nofollow">http://pastebin.com/wS32UNCq</a></p>