title: AngularJS watch variable in directive
body: <p>I have one problem.
  I'm using <a href="http://gregpike.net/demos/angular-local-storage/demo/demo.html" rel="nofollow">Angular localStoragee</a> module to store settings, which i set in controller with:</p>
  
  <pre><code>localStorageService.set('localStorageKey','Add this!');
  </code></pre>
  
  <p>It's working very well but how can i watch localStorageKey for changes in directive, which takes it's value as a parameter?</p>
  
  <p>I tried something like:</p>
  
  <pre><code>.directive('fooBar', function(localStorageService){
      var linker = function(scope, element, attrs){
  
          var unit = localStorageService.get('localStorageKey');
          $watch('unit', function(){
              console.log(unit);
          });
  
      }
  
      return {
          restrict: 'AE',
          scope: {
              value: '@dataValue'
          },
          replace: true,
          link: linker
      }
  });
  </code></pre>
  
  <p>But no luck, i don't think i can watch variables like this. How can i solve this problem?</p>
  
  <p>Thanks.</p>