The meeting sort of started with me ,Darren, and John from BradLUG waiting for the rest of you in the entrance to the Adelphi. By about 7:30pm most of you who stayed for the meeting had arrived.
Topics of discussion included
Taking a fortnight to download a copy of slackware in the days of phone-line modem connections.
How big Leeds DevOps is now.
How cheap computers are getting.
The way they teach computing – esp Linux in France, thanks Jean-Jaques
Why Leeds is a good place to work in computing.
Most of us boggled at eachother’s tablets, and my substitute for a tablet -a camera that cost me less than a beer!
By ~9pm I had to depart.
Every Python programmer knows to avoid mutable default arguments:def fn(mutable=): mutable.append('elem') print mutable fn() fn() $ python test.py ['elem'] ['elem', 'elem']
However, many are not clear that this is due to arguments being evaluated at import time, rather than the first time the function is evaluated.
This results in related quirks such as:def never_called(error=1/0): pass $ python test.py Traceback (most recent call last): File "test.py", line 1, in <module> ZeroDivisionError: integer division or modulo by zero
... and an—implementation-specific—quirk caused by naive constant folding:def never_called(): 99999999 ** 9999999 $ python test.py [hangs]
I suspect that this can be used as denial-of-service vector.
This month sees us in the Adelphi, just South of Leeds Bridge, Starting around 7pm-ish. One of the regulars, Andy, has offered to show us round a nearby data centre, during the meeting.
Here is a location link from google maps Look for the funny blokes sitting round the laptops, see you there!