替換所有連續重復值的出現

Question

我有一個重復連續昏迷的字符串，我想在昏迷之間插入一個字符，例如零。 當我運行re.sub它返回的是：

re.sub(r",,", ",0," , "a,,,,,,,,,,,,,a",)
'a,0,,0,,0,,0,,0,,0,,a'

我想要的結果就是所有的替換，比如：

'a,0,0,0,0,0,0,0,0,0,0,0,0,a'

我理解為什么會發生這種情況，模式中存在重疊，但我不知道如何解決它。

Answer 1

您可以使用前瞻匹配逗號后跟另一個逗號，並將匹配替換為",0" ，例如：

>>> re.sub(r",(?=,)", ",0", "a,,,,,,,,,,,,,a")
'a,0,0,0,0,0,0,0,0,0,0,0,0,a'

或者沒有正則表達式：

>>> ",".join(x or "0" for x in "a,,,,,,,,,,,,,a".split(","))
'a,0,0,0,0,0,0,0,0,0,0,0,0,a'

Answer 2

這實現了預期的結果：

In [1]: re.sub(r",,", ",0,0" , "a,,,,,,,,,,,,,a",)
Out[1]: 'a,0,0,0,0,0,0,0,0,0,0,0,0,a'