How to remove specific characters in a string within specific delimiters, e.g. within parentheses

Question

In the string

my_string = 'abcd (ef gh ) ij'

I need to remove the spaces only when they appear within parentheses, resulting in:

my_clean_string = 'abcd (efgh) ij'

This post suggests how to remove all parentheses text entirely via re.sub(r'\([^)]*\)', '', my_string), however I do not know how specify the removal should only be applied to whitespaces ' '.

Is there a regexpr (or simple python) solution that does this without looping through each character expressly?

Mazdak · Accepted Answer · 2017-01-15T08:33:48.190

2

Here is one general way that will work for nested parenthesis as well:

In [27]: my_string = 'abcd (  ()e(e w  )f ) gh'

In [28]: re.sub(r' \(\s+|\s+\)', lambda x: x.group().strip(), my_string)
Out[28]: 'abcd(()e(e w)f) gh'

If you want to remove spaces even between words you can play around with look-arounds ;-):

In [40]: my_string = 'abcd (  ()e(e w  )f ) gh'

In [41]: re.sub(r'\s+(?=[^[\(]*\))|((?<=\()\s+)', '', my_string)
Out[41]: 'abcd (()e(ew)f) gh'

edited Jan 15 '17 at 08:33

answered Jan 14 '17 at 12:53

Mazdak

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Can you remove also spaces between words within the parentheses? – Pythonic Jan 14 '17 at 12:56
@Kasramvd split and join works for your nested regex also. Update it. – Mohammad Yusuf Jan 14 '17 at 13:25
@MYGz [Now you have two problems](https://blog.codinghorror.com/regular-expressions-now-you-have-two-problems/) :-) – Mazdak Jan 14 '17 at 14:23

Mohammad Yusuf · Answer 2 · 2017-01-14T13:23:34.600

1

This will remove spaces in front and behind the words inside the parenthesis.

import re
my_string = 'abcd (   ef dfg dfg  ) gh'
print re.sub('\(\s*(.*?)\s*\)', lambda x: ''.join(x.group().split()), my_string, re.DOTALL)

Output:

abcd (efdfgdfg) gh

edited Jan 14 '17 at 13:23

answered Jan 14 '17 at 12:46

Mohammad Yusuf

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I need to remove all spaces, included between words, example `abcd (efdfgdfg) gh` in your case – Pythonic Jan 14 '17 at 12:55
@Pythonic Updated. – Mohammad Yusuf Jan 14 '17 at 13:16
@Pythonic for considering newlines you can use `re.DOTALL` – Mohammad Yusuf Jan 14 '17 at 13:23

score 0 · Answer 3 · edited Jan 14 '17 at 13:04

0

a solution without using regex,

my_string = 'abcd (ef ) gh'
str_to_replace = my_string[my_string.find('(')+1:my_string.find(')')]
out = my_string.replace(str_to_replace,str_to_replace.replace(' ',''))

Result

abcd (ef) gh

edited Jan 14 '17 at 13:04

das-g

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answered Jan 14 '17 at 12:50

Rahul K P

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score 0 · Answer 4 · edited May 23 '17 at 12:08

0

Relating from this post,

re.sub("\\s+(?=[^()]*\\))", "", my_string)

edited May 23 '17 at 12:08

Community

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answered Jan 14 '17 at 13:01

Pythonic

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This won't work with strings like `'abcd ( ()e(e w )f ) gh'` – Mazdak Jan 14 '17 at 13:02

How to remove specific characters in a string *within specific delimiters*, e.g. within parentheses

4 Answers4

How to remove specific characters in a string within specific delimiters, e.g. within parentheses