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Implementing slicing in __getitem__
... a slice object when the object is sliced. Simply look at the start, stop, and step members of the slice object in order to get the components for the slice.
>>> class C(object):
... def __getitem__(self, val):
... print val
...
>>> c = C()
>>> c[3]
3
>>> ...
What is __declspec and when do I need to use it?
... seen instances of __declspec in the code that I am reading. What is it? And when would I need to use this construct?
6 A...
What does the “yield” keyword do?
What is the use of the yield keyword in Python, and what does it do?
42 Answers
42
...
How can i query for null values in entity framework?
...If this bug has affected you too, please visit the bug report on UserVoice and let Microsoft know that this bug has affected you as well.
Edit: This bug is being fixed in EF 4.5! Thanks everyone for upvoting this bug!
For backwards compatibility, it will be opt-in - you need manually enable a s...
How to get the parent dir location
...with dirname or joining or any of that. Just treat __file__ as a directory and start climbing:
# climb to __file__'s parent's parent:
os.path.abspath(__file__ + "/../../")
That's far less convoluted than os.path.abspath(os.path.join(os.path.dirname(__file__),"..")) and about as manageable as dirn...
What is the best way to implement nested dictionaries?
...ython?
This is a bad idea, don't do it. Instead, use a regular dictionary and use dict.setdefault where apropos, so when keys are missing under normal usage you get the expected KeyError. If you insist on getting this behavior, here's how to shoot yourself in the foot:
Implement __missing__ on a di...
Catch a thread's exception in the caller thread in Python
I'm very new to Python and multithreaded programming in general. Basically, I have a script that will copy files to another location. I would like this to be placed in another thread so I can output .... to indicate that the script is still running.
...
PATH issue with pytest 'ImportError: No module named YadaYadaYada'
I used easy_install to install pytest on a mac and started writing tests for a project with a file structure likes so:
20 A...
Python: Bind an Unbound Method?
...descriptors, so you can bind them by calling their __get__ method:
bound_handler = handler.__get__(self, MyWidget)
Here's R. Hettinger's excellent guide to descriptors.
As a self-contained example pulled from Keith's comment:
def bind(instance, func, as_name=None):
"""
Bind the functi...
Is it safe to push_back an element from the same vector?
...s problem (or something very similar to it) as a potential defect in the standard:
1) Parameters taken by const reference can be changed during execution
of the function
Examples:
Given std::vector v:
v.insert(v.begin(), v[2]);
v[2] can be changed by moving elements of vect...