Searching and replacing text ?

[Larry Bates]

Oltmans wrote:
> Hi,
> 
> I'm new to Python (and admittedly not a very good programmer) and I've
> come across a scenario where I've to search and replace text in a
> file.
> 
> For the sake of an example, I'm searching for every occurence of the
> text
> [[http://www.hotmail.com -> Hotmail]]
> 
> I've to replace it with
> [http://www.hotmail.com Hotmail]
> 
> I've come up with following scheme
> p=re.compile(r'\[\[')
> q=re.compile(r'->')
> 
> p.sub('[',txt)
> q.sub('\b',txt)
> 
> Give that I don't have very strong RegEX background, this doesn't look
> very elegant. Is there some other way I can accomplish the same thing?
> Moreover, please note that I'm using 'p' and 'q' for two regex and
> then calling 'sub()' on both p and q. Can't I just do that by
> employing one RegEx and then calling sub() only once?
> 
> Please enlighten me. Thanks in advance.
> 

If you really want to replace EVERY occurrence, no regexes are needed.
I'd do something like (not tested):

fp=open(inputfilename, 'r')
contents=fp.read()
fp.close()
parts=contents.split('[[http://www.hotmail.com -> Hotmail]]')
newcontents='[http://www.hotmail.com Hotmail]'.join(parts)
fp=open(outputfilename, 'w')
fp.write(newcontents)
fp.close()

-Larry