public function grant($ability) {
    if (!in_array($ability, $this->abilities)) {
      return $this->abilities = array_merge([$ability], $this->abilities);
    }
    return true;
  }
public function grant($ability) {
    if (!in_array($ability, $this->abilities)) {
      return $this->abilities = array_merge([$ability], $this->abilities);
    }
    return true;
  }
public function grant ( $ ability ) { if ( ! in_array ( $ ability , $ this -> abilities ) ) { return $ this -> abilities = array_merge ( [ $ ability ] , $ this -> abilities ) ; } return true ; }
Grant an ability.

@param string $ability The ability.
Grant an ability .