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How does the main() method work in C?

...d nothing bad happens with their given compiler. This is the case if the calling conventions are such that: The calling function cleans up the arguments. The leftmost arguments are closer to the top of the stack, or to the base of the stack frame, so that spurious arguments do not invalidate the ...
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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 ...
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What are rvalues, lvalues, xvalues, glvalues, and prvalues?

...e they needed? Probably not if we wish to forfeit the new features. But to allow better optimization we should probably embrace them. Quoting n3055: An lvalue (so-called, historically, because lvalues could appear on the left-hand side of an assignment expression) designates a function or an obj...
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What is a clean, pythonic way to have multiple constructors in Python?

... Actually None is much better for "magic" values: class Cheese(): def __init__(self, num_holes = None): if num_holes is None: ... Now if you want complete freedom of adding more parameters: class Cheese...
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What are OLTP and OLAP. What is the difference between them?

...storical data) use OLAP if you are doing transactions (ex. adding/removing orders on an e-commerce cart) use OLTP Short answer: Let's consider two example scenarios: Scenario 1: You are building an online store/website, and you want to be able to: store user data, passwords, previous transact...
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Determine the type of an object?

...object, and isinstance() to check an object’s type against something. Usually, you want to use isistance() most of the times since it is very robust and also supports type inheritance. To get the actual type of an object, you use the built-in type() function. Passing an object as the only param...
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Iterate an iterator by chunks (of n) in Python? [duplicate]

...y_list[i:i + chunk_size] for i in range(0, len(my_list), chunk_size)] Finally, a solution that works on general iterators an behaves as desired is def grouper(n, iterable): it = iter(iterable) while True: chunk = tuple(itertools.islice(it, n)) if not chunk: return...
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Vertically align an image inside a div with responsive height

...ation to the first-child and our element (the image) both. 3) Finally, in order to remove the white space character between inline(-block) elements, we could set the font size of the parent to zero by font-size: 0;. Note: I used Nicolas Gallagher's image replacement technique in the following. Wh...
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Is it possible to declare two variables of different types in a for loop?

...and clang for years (since gcc-7 and clang-4.0) (clang live example). This allows us to unpack a tuple like so: for (auto [i, f, s] = std::tuple{1, 1.0, std::string{"ab"}}; i < N; ++i, f += 1.5) { // ... } The above will give you: int i set to 1 double f set to 1.0 std::string s set to "...
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How do you do Impersonation in .NET?

...asy WindowsIdentity.Impersonate Method (check out the code samples) Basically you will be leveraging these classes that are out of the box in the .NET framework: WindowsImpersonationContext WindowsIdentity The code can often get lengthy though and that is why you see many examples like the on...