Re: Handling 3 operands in an expression without raising an exception

[Νίκος]

Στις 26/9/2013 1:41 μμ, ο/η Antoon Pardon έγραψε:
Op 26-09-13 12:18, Νίκος schreef:
Στις 26/9/2013 1:12 μμ, ο/η Antoon Pardon έγραψε:
Op 26-09-13 11:56, Νίκος schreef:
Στις 26/9/2013 11:55 πμ, ο/η Nobody έγραψε:
On Thu, 26 Sep 2013 10:26:48 +0300, Νίκος wrote:
How can i wrote the two following lines so for NOT to throw out
KeyErrors when a key is missing?

city = gi.time_zone_by_addr( os.environ['HTTP_CF_CONNECTING_IP'] ) or
gi.time_zone_by_addr( os.environ['REMOTE_ADDR'] ) or
"Άγνωστη Πόλη"

tz = None
ip = os.environ.get('HTTP_CF_CONNECTING_IP')
if ip:
     tz = gi.time_zone_by_addr(ip)
if not tz:
     ip = os.environ.get('REMOTE_ADDR')
     if ip:
       tz = gi.time_zone_by_addr(ip)
if not tz:
     tz = "ÎγνÏÏÏη Î Ïλη"

Likewise for the hostname.


Its logic is simple and straightforward but too many lines:

host = socket.gethostbyaddr( os.environ.get('HTTP_CF_CONNECTING_IP') or
os.environ.get('REMOTE_ADDR') or  "Άγνωστη Προέλευση" )

this is much better in my opinion and straighforward also and more clear
to read:

No it is not and you prove that in the very next line.

it doens't work though:

If it doesn't do what you think it should do then it is not straight
forward or clear, at least not to you.

It is far better than the ifs, even easier to read, i was just missing a
[0] at the end.

host = socket.gethostbyaddr( os.environ.get('HTTP_CF_CONNECTING_IP') or
os.environ.get('REMOTE_ADDR') or  "Άγνωστη Προέλευση" )[0]

No it is not. Your purpose was to have a line that wouldn't throw an
exception even if some environ variables were not available. That
means it shouldn't throw an exception when I execute the code. Guess
what happens:

socket.gethostbyaddr( os.environ.get('HTTP_CF_CONNECTING_IP') or
os.environ.get('REMOTE_ADDR') or  "Άγνωστη Προέλευση" )[0]
Traceback (most recent call last):
   File "<stdin>", line 1, in <module>
socket.gaierror: [Errno -2] Name or service not known

You are just illustrating your lack of basic understaning.

I'm surepirsed, becaus eon my domain [superhost.gr] the same lien of 
code works withnout an error and it display the 'host' fileds properly.

Perhaps its failing via shell or you do not have a web server installed 
to prepare the enviromental variables or i dont know what else to hink.

But in my website this code runs at the probelm with no problem.

--
https://mail.python.org/mailman/listinfo/python-list