regex in python 2.4

Question

I have a string in python as below:

"\\B1\\B1xxA1xxMdl1zzInoAEROzzMofIN"

I want to get the string as

"B1xxA1xxMdl1zzInoAEROzzMofIN"

I think this can be done using regex but could not achieve it yet. Please give me an idea.

Sorry, I updated the question. I meant python 2.4. Sorry again. — gishara, Jan 06 '12 at 07:57
Do you mean you want to remove all the cars between the two backslashes \? — JMax, Jan 06 '12 at 08:01
Why are you using Python 2.4? This is now nearly a decade old... — Tim Pietzcker, Jan 06 '12 at 08:16
Is this result of `print` or `repr` statement? In other words: is `\\` a representation of one character or two? — Tadeck, Jan 06 '12 at 08:17

RanRag · Accepted Answer · 2012-01-06T08:09:31.483

3

st = "\B1\B1xxA1xxMdl1zzInoAEROzzMofIN"
s = re.sub(r"\\","",st)
idx = s.rindex("B1")
print s[idx:]

output = 'B1xxA1xxMdl1zzInoAEROzzMofIN'

OR

st = "\B1\B1xxA1xxMdl1zzInoAEROzzMofIN"
idx = st.rindex("\\")
print st[idx+1:]

output = 'B1xxA1xxMdl1zzInoAEROzzMofIN'

edited Jan 06 '12 at 08:09

answered Jan 06 '12 at 08:02

RanRag

These look a bit too specific for me. What if the source is `"123\\456\\789"` - neither solution will give `"123789"` as a result. – Tim Pietzcker Jan 06 '12 at 08:15
his example was specific too, so i came with this specific solution. I thought he was facing problem with this specific string. – RanRag Jan 06 '12 at 08:22
Thanks a lot RanRag. The second solution what I needed. – gishara Jan 06 '12 at 09:59
1

Note that this will work if you have **only one** double backslash. Yet, for this case, using list slicing is simple and efficient. – JMax Jan 06 '12 at 13:27

score 3 · Answer 2 · edited May 23 '17 at 11:45

3

Here is a try:

import re
s = "\\B1\\B1xxA1xxMdl1zzInoAEROzzMofIN"
s = re.sub(r"\\[^\\]+\\","", s)
print s

Tested on http://py-ide-online.appspot.com (couldn't find a way to share though)

[EDIT] For some explanation, have a look at the Python regex documentation page and the first comment of this SO question:

because using brackets [] can be tricky (IMHO)

In this case, [^\\] means anything but two backslashes \\.

So [^\\]+ means one or more character that matches anything but two backslashes \\.

edited May 23 '17 at 11:45

Community

answered Jan 06 '12 at 08:12

JMax

You make `\w` optional, and they may not be word chars, why not replace `\w*` with `[^\\]+`? You'd then have a general pattern – fge Jan 06 '12 at 08:40
@fge: thanks for the suggestion, I've edited my answer with your code (it took me some time to check this as I am not that familiar to Python Regex) – JMax Jan 06 '12 at 08:50

score 0 · Answer 3 · answered Jan 06 '12 at 09:49

0

If the desired section of the string is always on the RHS of a \ char then you could use:

string = "\\B1\\B1xxA1xxMdl1zzInoAEROzzMofIN"
string.rpartition("\\")[2]

output = 'B1xxA1xxMdl1zzInoAEROzzMofIN'

answered Jan 06 '12 at 09:49

Alex L

3 Answers3