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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
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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...
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...
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.
...
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...
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...
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...
What is the difference between class and instance attributes?
...
Only the mutable types are shared. Like for int and str they still attached with each instances rather than class.
– Babu
Jul 17 '14 at 11:59
11
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How do I override __getattr__ in Python without breaking the default behavior?
...oo has no attribute called bar. If the attribute is one you don't want to handle, raise AttributeError:
class Foo(object):
def __getattr__(self, name):
if some_predicate(name):
# ...
else:
# Default behaviour
raise AttributeError
However, un...