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[Python-Dev] PEP 3144 review.

R. David Murray rdmurray at bitdance.com
Wed Sep 16 17:25:09 CEST 2009 
On Wed, 16 Sep 2009 at 12:50, exarkun at twistedmatrix.com wrote:
> On 11:10 am, ncoghlan at gmail.com wrote:
>> Or, to put it another way, given an arbitrary host in a network (e.g.
>> your own machine or the default gateway) and the netmask for that
>> network, calculate the network address.
>> 
>> With a "lax" parser on IPNetwork this is a trivial task - just create
>> the network object and then retrieve the network address from it.
>> 
>> If, on the other hand, IPNetwork demands that you already know the
>> network address before allowing you to create an IPNetwork object, then
>> you're pretty much out of luck - if all you have to work with are the IP
>> strings then this is actually a tricky calculation.
>> 
>> If the default IPNetwork constructor was made more strict, then this
>> functionality would have to be made available another way (probably as
>> an alternate constructor like IPNetwork.from_host_address rather than as
>> a boolean 'strict' option)
>
> This seems to be the right solution to me, particularly the use of an 
> alternate constructor rather than an ambiguously named flag.

+1

--David
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