[Python-Dev] PEP 3144 review. (original) (raw)

"Martin v. Löwis" martin at v.loewis.de
Mon Sep 28 22:11:01 CEST 2009

Martin v. Löwis <martin v.loewis.de> writes:

Could you explain what benefit there is for allowing the user to create network objects that don't represent networks? Is there a use-case where these networks-that-aren't-networks are something other than a typo? Under what circumstances would I want to specify a network as 192.168.1.1/24 instead of 192.168.1.0/24?

[...] So Python code has to make the computation, and it seems most natural that the IP library is the piece of code that is able to compute a network out of that input. The thing is, it doesn't create a network, it creates a hybrid "network plus host" which retains knowledge about the original host (that is, 192.168.1.1 rather than simply 192.168.1.0, if you enter "192.168.1.1/24"). That's what the OP meant with "networks-that-aren't-networks", and that's what people are objecting to.

That's not the question that was asked, though - the question asked was "Under what circumstances would I want to specify...". I hope most people agree that it is desirable to be able to specify a network not just by its network address.

Regards, Martin

More information about the Python-Dev mailing list