re.sub() - Substitute Matches with String

Q

How to substitutes matches of a regular expression in a target string with another string using re.sub()?

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A

The re.sub() function allows you to substitute (or replace) matches of a given regular expression in match the beginning part of a target string with of a given regular expression.

import re
f = re.sub(pattern, repl, string, count=0, flags=0)

Where:
   pattern is the regular expression
   repl is the replacement string
   string is the target string
   count=0 means replacing all matches
   f is the final string after replacements are done

Here is Python example that shows you how to use the re.findall() function:

>>> import re
>>> s = "Hello perl.org, php.net, and python.org!"
>>> p = "(\\w+)\\.(\\w+)"
>>> print(p)
(\w+)\.(\w+)
>>> r = "domain"
>>> f = re.sub(p,r,s)
>>> print(f)
Hello domain, domain, and domain!

 

Use Match Group \g<n> in Replacement

re.match() - Match from String Beginning

're' Module - Regular Expression Operations

⇑⇑ Python Tutorials

2018-10-19, 1694🔥, 0💬