PHP Group: Code Correction

gistfile1.php

public function check($username)
{
  static $rule=null;
  if(is_null($rule))
  {
    $rule = [$username => 'unique:login']; 
  }
  //$validation=Validator::make(array([$username=>$username]),$rule);
  $validation=Validator::make(array(['username'=>$username]), $rule);
  if($validation->passes())
  {
    return 'User is registerd';
  }
  return 'username is available';
}

Great job