filesystem.py 文件源码

def flat(parts):
    if isinstance(parts, str):
        if os.path.isabs(parts):
            raise ValueError('Path must be relative. '
                             '[{}]'.format(parts))
        yield parts
    elif isinstance(parts, PurePath):
        if parts.is_absolute():
            raise ValueError('Path must be relative. '
                             '[{}]'.format(parts))
        yield parts
    elif isinstance(parts, (list, tuple)):
        for p in parts:
            yield from flat(p)
    else:
        raise TypeError(
            'Key must be relative path [str or Path]. '
            'But {}'.format(parts))