Search and replace with "whole word only" option [duplicate]

Question

I have a script that runs into my text and search and replace all the sentences I write based in a database.

The script:

with open('C:/Users/User/Desktop/Portuguesetranslator.txt') as f:
    for l in f:
        s = l.split('*')
        editor.replace(s[0],s[1])

And the Database example:

Event*Evento*
result*resultado*

And so on...

Now what is happening is that I need the "whole word only" in that script, because I'm finding myself with problems.

For example with Result and Event, because when I replace for Resultado and Evento, and I run the script one more time in the text the script replace again the Resultado and Evento.

And the result after I run the script stays like this Resultadoado and Eventoo.

Just so you guys know.. Its not only for Event and Result, there is more then 1000+ sentences that I already set for the search and replace to work..

I don't need a simples search and replace for two words.. because I'm going to be editing the database over and over for different sentences..

Answer 1

You want a regular expression. You can use the token \b to match a word boundary: i.e., \bresult\b would match only the exact word "result."

import re

with open('C:/Users/User/Desktop/Portuguesetranslator.txt') as f:
    for l in f:
        s = l.split('*')
        editor = re.sub(r"\b%s\b" % s[0] , s[1], editor)

Answer 2

Use re.sub:

replacements = {'the':'a', 
                'this':'that'}

def replace(match):
    return replacements[match.group(0)]

# notice that the 'this' in 'thistle' is not matched 
print re.sub('|'.join(r'\b%s\b' % re.escape(s) for s in replacements), 
        replace, 'the cat has this thistle.') 

Prints

a cat has that thistle.

Notes:

• All the strings to be replaced are joined into a single pattern so that the string needs to be looped over just once.

• The source strings are passed to re.escape to make avoid interpreting them as regular expressions.

• The words are surrounded by r'\b' to make sure matches are for whole words only.

• A replacement function is used so that any match can be replaced.

Answer 3

Use re.sub instead of normal string replace to replace only whole words.So your script,even if it runs again will not replace the already replaced words.

>>> import re
>>> editor = "This is result of the match"
>>> new_editor = re.sub(r"\bresult\b","resultado",editor)
>>> new_editor
'This is resultado of the match'
>>> newest_editor = re.sub(r"\bresult\b","resultado",new_editor)
>>> newest_editor
'This is resultado of the match'

Answer 4

It is very simple. use re.sub, don't use replace.

import re
replacements = {r'\bthe\b':'a', 
                r'\bthis\b':'that'}

def replace_all(text, dic):
    for i, j in dic.iteritems():
        text = re.sub(i,j,text)
    return text

replace_all("the cat has this thistle.", replacements)

It will print

a cat has that thistle.