具有多个组的正则表达式? [英] RegEx with multiple groups?

问题描述

我对在 Python 中返回多个组感到困惑.我的正则表达式是这样的:

I'm getting confused returning multiple groups in Python. My RegEx is this:

lun_q = 'Lun:\s*(\d+\s?)*'

我的字符串是

s = '''Lun:                     0 1 2 3 295 296 297 298'''`

我返回一个匹配的对象，然后想查看组，但它显示的是最后一个数字(258):

I return a matched object, and then want to look at the groups, but all it shows it the last number (258):

r.groups()  
(u'298',)

为什么不返回 0,1,2,3,4 等组?

Why isn't it returning groups of 0,1,2,3,4 etc.?

推荐答案

你的正则表达式只包含一对括号(一个捕获组)，所以你的匹配中只能得到一个组.如果您在捕获组(+ 或 *)上使用重复运算符，则每次重复该组时该组都会被覆盖"，这意味着只有最后一个匹配是捕获.

Your regex only contains a single pair of parentheses (one capturing group), so you only get one group in your match. If you use a repetition operator on a capturing group (+ or *), the group gets "overwritten" each time the group is repeated, meaning that only the last match is captured.

在您的示例中，您最好将 .split() 与正则表达式结合使用:

In your example here, you're probably better off using .split(), in combination with a regex:

lun_q = 'Lun:\s*(\d+(?:\s+\d+)*)'
s = '''Lun: 0 1 2 3 295 296 297 298'''

r = re.search(lun_q, s)

if r:
    luns = r.group(1).split()

    # optionally, also convert luns from strings to integers
    luns = [int(lun) for lun in luns]

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