public function is($type = null)
    {
        if ($type === null) {
            return $this->is;
        } else {
            return $type == $this->is;
        }
    }
public function is($type = null)
    {
        if ($type === null) {
            return $this->is;
        } else {
            return $type == $this->is;
        }
    }
public function is ( $ type = null ) { if ( $ type === null ) { return $ this -> is ; } else { return $ type == $ this -> is ; } }
Retrieve the type of object this asset is, or test it's type

@return string
Retrieve the type of object this asset is or test it s type