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Check for null in foreach loop
...s; everything else is going to involve much more work (tests, assignments, extra method calls, unnecessary GetEnumerator(), MoveNext(), Dispose() on the iterator, etc).
An if test is simple, obvious, and efficient.
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Python executable not finding libpython shared library
I am installing Python 2.7 on CentOS 5. I built and installed Python as follows
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Getting the last element of a list
...at should happen when attempting to get an element from an empty list. For Strings astr[-1:] could be a valid approach since it returns the same type as astr[-1], but I don't think the ':' helps to deal with empty lists (and the question is about lists). If the idea is to use "alist[-1:]" as a condi...
Checking for empty queryset in Django
...if not my_objects: to demonstrate that this is how they do it in the docs. All else is utterly irrelevant so I do not get your point. They could as well make a thousand queries and it would still be totally irrelevant as this is not the point of this answer, with which I make clear that I agree.
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Keyboard Interrupts with python's multiprocessing Pool
...s to set up the worker processes to ignore SIGINT altogether, and confine all the cleanup code to the parent process. This fixes the problem for both idle and busy worker processes, and requires no error handling code in your child processes.
import signal
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def init_worker():
signal.sign...
In git how is fetch different than pull and how is merge different than rebase?
...s much cleaner than doing a normal pull with merging, which will create an extra commit with the merges.
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Check if event exists on element [duplicate]
...econd argument feed 'events' and that will return an object populated with all the events such as 'click'. You can loop through that object and see what the event handler does.
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What is the difference between Bower and npm?
...oject repo (while developing), or get them via CDN. Now, you can skip that extra download weight in the repo, and somebody can do a quick bower install and instantly have what they need, locally.
If a Bower dependency then specifies its own dependencies in its bower.json, those'll be downloaded for ...
How to copy to clipboard in Vim?
... As an addendum to your note - you may also have to install extra packages to get this to work. If your vim lacks the +xterm_clipboard feature (visible when you run vim --version). This was the case for me (running Kubuntu 12.10). I had to install the vim-gui-common package to get the...
Node.js / Express.js - How does app.router work?
...use is app.use() . When the middleware is being executed, it will either call the next middleware by using next() or make it so no more middleware get called. That means that the order in which I place my middleware calls is important, because some middleware depends on other middleware, and some...