Generating and printing a range of ip addresses
tjreedy at udel.edu
Sat Feb 14 17:15:41 CET 2004
"Stephen Briley" <sdb1031 at yahoo.com> wrote in message
news:20040214073612.19320.qmail at web60910.mail.yahoo.com...
Major problem is bug in *your* code, minor problem is buglet in
> >>> from ipv4 import *
> >>> ip = IPv4('10.0.0.1')
> >>> startadd = ip.nexthost()
> >>> endadd = ('10.0.3.0')
You forgot IPv4 call, so endadd is str, not IPv4 instance! endadd =
> >>> print startadd
> >>> print endadd
> >>> while startadd != endadd:
> ... startadd = ip.nexthost()
> ... print startadd
> Traceback (most recent call last):
> File "<interactive input>", line 1, in ?
> File "C:\Python23\lib\ipv4.py", line 250, in __cmp__
> return cmp(self._address, other._address)
> AttributeError: 'str' object has no attribute '_address'
IPv4 should arguably catch mismatch and give better error message. Suggest
to IPv4 author that 'he' replace above with something like
if isinstance(other, IPv4):
return cmp(self._address, other._address)
raise TypeError('Can only compare IPv4 instance to another
He could use try/except/raise, but this would allow probably nonsensical
comparisons with non-IPv4 objects with _address attribute.
Terry J. Reedy
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