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Why is Python 3.x's super() magic?
In Python 3.x, super() can be called without arguments:
1 Answer
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Which method performs better: .Any() vs .Count() > 0?
...le<T> sequence.
For just IEnumerable<T>, then Any() will generally be quicker, as it only has to look at one iteration. However, note that the LINQ-to-Objects implementation of Count() does check for ICollection<T> (using .Count as an optimisation) - so if your underlying data-sou...
How update the _id of one MongoDB Document?
I want update an _id field of one document. I know it's not a really good pratice. But with some technical reason, I need update it. If I try to update it I get:
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Use numpy array in shared memory for multiprocessing
...
To add to @unutbu's (not available anymore) and @Henry Gomersall's answers. You could use shared_arr.get_lock() to synchronize access when needed:
shared_arr = mp.Array(ctypes.c_double, N)
# ...
def f(i): # could be anything numpy accepts as an index such another numpy array
with ...
Calling class staticmethod within the class body?
... def stat_func():
return 42
_ANS = stat_func.__func__() # call the staticmethod
def method(self):
ret = Klass.stat_func()
return ret
As an aside, though I suspected that a staticmethod object had some sort of attribute storing the original function, I had no ...
Hidden Features of PHP? [closed]
...and getting a reference most of the time is great.
– Allain Lalonde
Sep 14 '08 at 17:46
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This is...
Creating C macro with ## and __LINE__ (token concatenation with positioning macro)
...lizing) unless the result needs to be "stringified". Gcc has features but ALL can be done with plain C version 1 (and some argue Berkeley 4.3 C is so much faster it's worth learning how to use).
**Clang (llvm) DOES NOT DO WHITE SPACE CORRECTLY for macro expansion - it adds whitespace (which certai...
When would anyone use a union? Is it a remnant from the C-only days?
I have learned but don't really get unions. Every C or C++ text I go through introduces them (sometimes in passing), but they tend to give very few practical examples of why or where to use them. When would unions be useful in a modern (or even legacy) case? My only two guesses would be programming ...
StringBuilder vs String concatenation in toString() in Java
...o builder?
At the point where you're concatenating in a loop - that's usually when the compiler can't substitute StringBuilder by itself.
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Objective-C : BOOL vs bool
..., you can assume that BOOL is a char. You can use the (C99) bool type, but all of Apple's Objective-C frameworks and most Objective-C/Cocoa code uses BOOL, so you'll save yourself headache if the typedef ever changes by just using BOOL.
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