if not pathname:這種判斷有什么意義

venustef

def convert_path (pathname):
    """Return 'pathname' as a name that will work on the native filesystem,
    i.e. split it on '/' and put it back together again using the current
    directory separator.  Needed because filenames in the setup script are
    always supplied in Unix style, and have to be converted to the local
    convention before we can actually use them in the filesystem.  Raises
    ValueError on non-Unix-ish systems if 'pathname' either starts or
    ends with a slash.
    """
    if os.sep == '/':
        return pathname
    if not pathname:
        return pathname
    if pathname[0] == '/':
        raise ValueError, "path '%s' cannot be absolute" % pathname
    if pathname[-1] == '/':
        raise ValueError, "path '%s' cannot end with '/'" % pathname

    paths = string.split(pathname, '/')
    while '.' in paths:
        paths.remove('.')
    if not paths:
        return os.curdir
    return os.path.join(*paths)

請(qǐng)問(wèn)，這種代碼段是什么目的？什么情況下能走入這種代碼段？沒(méi)想到具體的場(chǎng)景
if not pathname:
        return pathname

if not paths:
        return os.curdir

substr函數(shù)

回復(fù) 1# venustef

if not pathname: ''

if not paths: '.'

venustef

回復(fù) 2# substr函數(shù)


    哦，明白了，就是為了要處理空串''和空l(shuí)ist []唄？多謝