Regex to remove specific words in python

Question

I want to do the some manipulation using regex in python.

So input is +1223,+12_remove_me,+222,+2223_remove_me and output should be +1223,+222

Output should only contain comma seperated words which don't contain _remove_me and only one comma between each word.

Note : REGEX which I tried \\+([0-9|+]*)_ , \\+([0-9|+]*) and some other combination using which I did not get required output.

Note 2 I can't use loop, need to do that without loop with regex only.

Answer 1

Your regex seems incomplete, but you were on the right track. Note that a pipe symbol inside a character class is treated as a literal and your [0-9|+] matches a digit or a | or a + symbols.

You may use

,?\+\d+_[^,]+

See the regex demo

Explanation:

• ,? - optional , (if the "word" is at the beginning of the string, it should be optional)
• \\+ - a literal +
• \\d+ - 1+ digits
• _ - a literal underscore
• [^,]+ - 1+ characters other than ,

Python demo :

import re
p = re.compile(r',?\+\d+_[^,]+')
test_str = "+1223,+12_remove_me,+222,+2223_remove_me"
result = p.sub("", test_str)
print(result)
# => +1223,+222

Answer 2

In your case you need regex with negotiation

[^(_remove_me)]

Demo

Answer 3

A non-regex approach would involve using str.split() and excluding items ending with _remove_me :

>>> s = "+1223,+12_remove_me,+222,+2223_remove_me"
>>> items = [item for item in s.split(",") if not item.endswith("_remove_me")]
>>> items
['+1223', '+222']

Or, if _remove_me can be present anywhere inside each item, use not in :

>>> items = [item for item in s.split(",") if "_remove_me" not in item]
>>> items
['+1223', '+222']

You can then use str.join() to join the items into a string again:

>>> ",".join(items)
'+1223,+222'

Answer 4

You could perform this without a regex, just using string manipulation. The following can be written as a one-liner, but has been expanded for readability.

my_string = '+1223,+12_remove_me,+222,+2223_remove_me' #define string
my_list = my_string.split(',')                         #create a list of words
my_list = [word for word in my_list if '_remove_me' not in word] #stop here if you want a list of words
output_string = ','.join(my_list)