string issue

[Terry Reedy]

"Steve Holden" <steve at holdenweb.com> wrote in message 
news:36QMd.103084$Jk5.36127 at lakeread01...
> You are modifying the list as you iterate over it. Instead, iterate over 
>  > a copy by using:
> for ip in ips[:]:

Or if you are only deleting items, you can iterate backwards.

You can also build a new list with only the items you want.  Do this either 
with an explicit loop or even better, use filter or a list comp.

ips = ['255.255.255.255', '128.173.120.79', '198.82.247.98',
'127.0.0.1', '255.0.0.0', '255', '128.173.255.34']

# 2.2 requires single char for 'not in string' test

ips2 = []
for ip in ips:
  if ip.find('255') == -1: ips2.append(ip)

print ips2
print filter(lambda ip: ip.find('255') == -1, ips)
print [ip for ip in ips if ip.find('255') == -1]

# thrice prints
['128.173.120.79', '198.82.247.98', '127.0.0.1']

This seems much more sensible to me than building a new list with 
everything (a copy), including things you don't want, and then deleting the 
things you don't want (an O(n**2) operation).

Terry J. Reedy