gistfile1.js

// in body ng-controller="MainCtrl as main"

this.app.controller('MainCtrl', function($scope) {
  this.first = "willy";
  this.last = "wonka";
  self = this;
  $scope.$watch('first + last', function(val) {
    self.fullName = self.first + ' ' + self.last
  });
  return this;
});