Imagine you have the following String:
"badger randomword badger mushroom mushroom somethingelse"
I want to keep the words "badger" and "mushroom", and replace every other word with "mushroom":
"badger mushroom badger mushroom mushroom mushroom"
But I can't find a regex to match "everything except the words badger and mushroom". Can you help me?
This will work
(?!\bbadger\b|\bmushroom\b)\b[^\s]+\b
Python Code
p = re.compile(r'(?!\bbadger\b|\bmushroom\b)\b[^\s]+\b')
test_str = "badger randomword badger mushroom mushroom somethingelse"
subst = "mushroom"
result = re.sub(p, subst, test_str)
A simple non-regex oneliner to perform this task would be -
new_string = ' '.join(word if word == 'badger' else 'mushroom' for word in original_string.split())
I would advise against using a complex regular expression here since Beautiful Is Better Than Ugly in Python.
You could use re.sub with function parameter which would make the pattern really simple:
import re
s = "badger randomword badger mushroom mushroom somethingelse"
re.sub('\w+', lambda x: 'badger' if x.group(0) == 'badger' else 'mushroom', s)
A non-regex solution (and much easier to read) would be this:
oldstring = "badger randomword badger mushroom mushroom somethingelse"
newstring = ""
for part in oldstring.split(" "):
if part in ["badger", "mushroom"]:
newstring += part
else:
newstring += "mushroom"
newstring += " "
newstring = newstring[:-1]
Try this
(?!badger\b)\b\w+\b
Explanation:
(?!…): Negative lookahead sample
\: Escapes a special character sample
\w: "word character": ASCII letter, digit or underscore sample
+: One or more sample
Python
import re
p = re.compile(ur'(?!badger\b)\b\w+\b')
test_str = u"badger randomword badger mushroom mushroom somethingelse"
subst = u"mushroom"
result = re.sub(p, subst, test_str)#badger mushroom badger mushroom mushroom mushroom
