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What does Python's eval() do?
...less until you find a need for it. It is used on sites like codepad.org to allow you to execute scripts in a test environment. eval() can also be used to execute highly-dynamic code, but you should make yourself fully aware of the security and performance risks before using it.
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Python Process Pool non-daemonic?
...to create a python Pool that is non-daemonic? I want a pool to be able to call a function that has another pool inside.
8 A...
Declaring variables inside or outside of a loop
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The scope of local variables should always be the smallest possible.
In your example I presume str is not used outside of the while loop, otherwise you would not be asking the question, because declaring it inside the while loop would not be an option, since it would not comp...
How to detect orientation change in layout in Android?
...ecreated when you switch to landscape. Instead, onConfigurationChanged is called. If this is undesired, you could use a variable to remember your activity's orientation and every time you go though onPause (for example) to check if the orientation is still the same.
– Elena
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Why is auto_ptr being deprecated?
...cs and the magic of rvalue references, it can do so considerably more naturally. It also "fits" with the rest of the standard library considerably better (though, in fairness, some of that is thanks to the rest of the library changing to accommodate move semantics instead of always requiring copying...
What is NSZombie?
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It's a memory debugging aid. Specifically, when you set NSZombieEnabled then whenever an object reaches retain count 0, rather than being deallocated it morphs itself into an NSZombie instance. Whenever such a zombie receives a message, it logs a warning rather ...
C++ performance vs. Java/C#
...p of a virtual machine which abstracts away the native architecture. Logically it would seem impossible for Java or C# to match the speed of C++ because of this intermediate step, however I've been told that the latest compilers ("hot spot") can attain this speed or even exceed it.
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Android应用内存泄露分析、改善经验总结 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...用，右键某个类→Merge Shortest Paths to GC Roots→exclude all phantom/weak/soft etc.references。
验证改善效果
  根据个人经验，我一般是这样验证改善效果的，运行程序，各个功能跑一遍，确保没有改出问题，完全退出程序，...
What is the difference between quiet NaN and signaling NaN?
...unit (FPU) or library if floating-point is implemented in software. A signalling NaN will produce a signal, usually in the form of exception from the FPU. Whether the exception is thrown depends on the state of the FPU.
C++11 adds a few language controls over the floating-point environment and pr...
How to add property to a class dynamically?
...ing on. Better late than never.
You can add a property to a class dynamically. But that's the catch: you have to add it to the class.
>>> class Foo(object):
... pass
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>>> foo = Foo()
>>> foo.a = 3
>>> Foo.b = property(lambda self: self.a + 1)
>>&...