正则表达式省略前导零

Question

I am trying to write a relatively simply function in Python that parses phone number. At the moment, the RegEx is giving me trouble. Namely, it omits leading zeroes, which I would like to keep.

How can I modify it so the leading zeroes are kept? The pattern also keeps 4 items in the end, which is undesired. At most three digits in the last block are desired.

phone_number = re.sub("(\d{3})(?=(\d)+(?!\d))", r"\1-", "%d" % int(clean_number[:-1])) + clean_number[-1]

What I would like is something like this:

Input: 00112223344 Output: 001-122-233-44

Answer 1

Try this -

phone_number  = re.sub(r'(\d{3})', r'\1-', phone_number)

It should work. Here is the demo