Replace all words from word list with another string in python

for-loop, python, replace, text

Solution

You can do that with a single call to `sub`:

big_regex = re.compile('|'.join(map(re.escape, prohibitedWords)))
the_message = big_regex.sub("repl-string", str(word[1]))

Example:

>>> import re
>>> prohibitedWords = ['Some', 'Random', 'Words']
>>> big_regex = re.compile('|'.join(map(re.escape, prohibitedWords)))
>>> the_message = big_regex.sub("<replaced>", 'this message contains Some really Random Words')
>>> the_message
'this message contains <replaced> really <replaced> <replaced>'

Note that using `str.replace` may lead to subtle bugs:

>>> words = ['random', 'words']
>>> text = 'a sample message with random words'
>>> for word in words:
...     text = text.replace(word, 'swords')
... 
>>> text
'a sample message with sswords swords'

while using `re.sub` gives the correct result:

>>> big_regex = re.compile('|'.join(map(re.escape, words)))
>>> big_regex.sub("swords", 'a sample message with random words')
'a sample message with swords swords'

As thg435 points out, if you want to replace words and not every substring you can add the word boundaries to the regex:

big_regex = re.compile(r'\b%s\b' % r'\b|\b'.join(map(re.escape, words)))

this would replace `'random'` in `'random words'` but not in `'pseudorandom words'`.

Problem

I have a user entered string and I want to search it and replace any occurrences of a list of words with my replacement string. ``` import re prohibitedWords = ["MVGame","Kappa","DatSheffy","DansGame","BrainSlug","SwiftRage","Kreygasm","ArsonNoSexy","GingerPower","Poooound","TooSpicy"] # word[1] contains the user entered message themessage = str(word[1]) # would like to implement a foreach loop here but not sure how to do it in python for themessage in prohibitedwords: themessage = re.sub(prohibitedWords, "(I'm an idiot)", themessage) print themessage ``` The above code doesn't work, I'm sure I don't understand how python for loops work.

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