How to replace multiple overlapping patterns with regex?

Question

I want to replace all occurrences of && with and.

For example, x&& && && should become x&& and and.

I tried re.sub(' && ', ' and ', 'x&& && && '), but it didn't work, the first && already consumed the whitespace so the second one didn't match.

Then I thought of non-capturing group and tried but failed again.

How can I solve this problem?

hwnd · Accepted Answer · 2015-09-04 03:34:26Z

3

You could use non-word boundaries here.

>>> re.sub(r'\B&&\B', 'and', 'x&& && &&')
'x&& and and'

answered Sep 4, 2015 at 3:34

hwnd

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Comments

vks · Accepted Answer · 2015-09-04 15:55:30Z

2

(?:^|(?<=\s))&&(?=\s|$)

Use lookarounds.Do not consume space just assert.See demo.

re.sub('(?:^|(?<=\s))&&(?=\s|$)', 'and', 'x&& && &&')

Output:'x&& and and'

answered Sep 4, 2015 at 3:34

vks

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the output of this code is 'x&& and and ', not 'x&& and and'

@pabtorre there was a typo.check now

Ramani Ganason · Accepted Answer · 2019-12-27 10:50:23Z

0

This seems like a very old post. Anyone looking for alternative can use the following regex as well.

re.sub(r"(\s)(\&\&)(?=(\s))", r"\1and", a)

answered Dec 27, 2019 at 10:50

Ramani Ganason

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