def _stringify(self, transform: StringifyTransform) -> str:
    res = []
    if self.rooted:
        res.append('::')
    res.append('delete ')
    if self.array:
        res.append('[] ')
    res.append(transform(self.expr))
    return ''.join(res)
def _stringify(self, transform: StringifyTransform) -> str:
    res = []
    if self.rooted:
        res.append('::')
    res.append('delete ')
    if self.array:
        res.append('[] ')
    res.append(transform(self.expr))
    return .join(res)