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What are dictionary view objects?
...eritems() returns an iterator over the dictionary’s (key, value) pairs.
Now take the following example to see the difference between an interator of dict and a view of dict
>>> d = {"x":5, "y":3}
>>> iter = d.iteritems()
>>> del d["x"]
>>> for i in iter: print...
Adding days to a date in Python
...ng it is a dumb idea? What is datetime? You can't rely on convention to know, but always have to look at the imports.
– Xiong Chiamiov
Jun 5 '17 at 17:47
10
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if A vs if A is not None:
...
@cedbeu, Seems to depend on the value of A. I tested now python -m timeit -s"a=0" "if a: pass" "else: pass" is faster than python -m timeit -s"a=0" "if a is None: pass" "else: pass" but python -m timeit -s"a=1" "if a: pass" "else: pass" is slower. Might be platform dependant, s...
What is the meaning of single and double underscore before an object name?
...but rather the ("organizing") public methods such as put and get (this is known as the Template Method design pattern -- see e.g. here for an interesting presentation based on a video of a talk of mine on the subject, with the addition of synopses of the transcript).
Edit: The video links in the de...
How to watch for array changes?
... a catch-all sounds appealing, just replace myArray with Array.prototype.
Now, that's just one method and there are lots of ways to change array content. We probably need something more comprehensive...
2. Create a custom observable array
Rather than overriding methods, you could create your own ...
How do you do a limit query in JPQL or HQL?
...
Old post I know. I fully agree with Rachel. Using NHibernate (.Net port of Hibernate), I've recently upgraded from 2 to 3 and same thing, top X is now throwing a parser error. However, when I added setMaxResults on the query, it did gene...
What are the best JVM settings for Eclipse? [closed]
...ill still look for the "Sun Microsystems" string, but with 6u21b7, it will now work - again.
For now, I still keep the -XX:MaxPermSize version (because I have no idea when everybody will launch eclipse the right JDK).
Implicit `-startup` and `--launcher.library`
Contrary to the previous settin...
How to make a Python script run like a service or daemon in Linux
...ike so:
import os, sys
fpid = os.fork()
if fpid!=0:
# Running as daemon now. PID is fpid
sys.exit(0)
Of course you also need to implement an endless loop, like
while 1:
do_your_check()
sleep(5)
Hope this get's you started.
...
How to detect iPhone 5 (widescreen devices)?
I've just upgraded to XCode 4.5 GM and found out that you can now apply the '4" Retina' size to your view controller in the storyboard.
...
Difference between reduce and foldLeft/fold in functional programming (particularly Scala and Scala
...rList.foldLeft(0)(_ + _))
Took 2589.363031 milli seconds
reduce vs fold
Now this is where it gets a little closer to the FP / mathematical roots, and a little trickier to explain. Reduce is defined formally as part of the MapReduce paradigm, which deals with orderless collections (multisets), Fo...