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From: ram@zedat.fu-berlin.de (Stefan Ram)
Newsgroups: comp.lang.python
Subject: Re: Correct syntax for pathological re.search()
Date: 7 Oct 2024 13:56:51 GMT
Organization: Stefan Ram
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"Michael F. Stemper" <michael.stemper@gmail.com> wrote or quoted:
> if not re.search("\\sout\{", line):

  So, if you're not down to slap an "r" before your string literals,
  you're going to end up doubling down on every backslash.

  Long story short, those double backslashes in your regex?
  They'll be quadrupling up in your Python string literal!

  main.py

import re

lines = r'''
abcdef
\sout{abcdef
abcdef
abc\sout{def
abcdef
abcdef\sout{
abcdef
'''.strip().split( '\n' )

for line in lines:
    product = re.search( "\\\\sout\\{", line )
    if not product:
        print( line )
    
  stdout

abcdef
abcdef
abcdef
abcdef