On Tue, Mar 17, 2009 at 7:01 AM, spir <denis.s...@free.fr> wrote:
> Is there a list.replace builtin I cannot find? Or a workaround?
Just assign directly to list elements. To replace s1 with s2 in l:
for i, x in enumerate(l):
if x == s1:
l[i] = s2
> Also: How would perform string.swap(s1, s2) in the following cases:
>
> * There is no secure 'temp' char, meaning that
> s.replace(s1,temp).replace(s2,s1).replace(temp,s2)
> will fail because any char can be part of s.
You could use re.sub() with a function for the replacement string. It
takes a little setup but it's not really difficult:
import re
def string_swap(s, s1, s2):
''' Swap s1 and s2 in s'''
# Given a match, return s2 for s1 and vice-versa
def replace(m):
return s2 if m.group()==s1 else s1
# re to match s1 or s2
matcher = re.compile('%s|%s' % (re.escape(s1), re.escape(s2)))
return matcher.sub(replace, s)
print string_swap('go to the park', 'o', 'a')
Kent
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