/**
  * List out all the permissions of all users.
  *
  * @todo  Refactor out mapping to a trait.
  *
  * @return \Illuminate\Contracts\View\View
  */
 public function index()
 {
     $permissions = collect(['*', 'admin.*', 'api.*']);
     $users = $this->user->all()->map(function ($user) use($permissions) {
         $user->permissions = collect([]);
         $permissions->map(function ($permission) use($user) {
             $user->permissions->push($this->buildPermissibleLookup($user, $permission));
         });
         return $user;
     });
     return view('gate-admin::permissions.index', compact('users'));
 }