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How do you trigger a block after a delay, like -performSelector:withObject:afterDelay:?

...ion of my block for 10 seconds. dispatch_after(dispatch_time(DISPATCH_TIME_NOW, 10 * NSEC_PER_SEC), dispatch_get_main_queue(), ^{ NSLog(@"parameter1: %d parameter2: %f", parameter1, parameter2); }); More: https://developer.apple.com/documentation/dispatch/1452876-dispatch_after ...
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C++ equivalent of java's instanceof

...seClass>(ptr)) { ... } However, this purely operates on the types as known by the compiler. Edit: This code should work for polymorphic pointers: template<typename Base, typename T> inline bool instanceof(const T *ptr) { return dynamic_cast<const Base*>(ptr) != nullptr; } E...
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Python nested functions variable scoping [duplicate]

... +1 I was confused, but now I see what happens. I'm a c# programmer and every time I begin to like Python something like this comes up and ruins it for me. – nima Dec 19 '12 at 14:14 ...
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What's the difference between using CGFloat and float?

... to make your app 64-bit clean and try running it as such, since most Macs now have 64-bit CPUs and Snow Leopard is fully 64-bit, including the kernel and user applications. Apple's 64-bit Transition Guide for Cocoa is a useful resource. ...
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C# operator overload for `+=`?

...ist, which are compiled in a special method calls, and CLR itself doesn't know anything about operators. So let's see what exactly stays behind the + and += operators. See this simple code: Decimal d = 10M; d = d + 10M; Console.WriteLine(d); Let view the IL-code for this instructions: IL_0000...
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How to validate an e-mail address in swift?

Does anyone know how to validate an e-mail address in Swift? I found this code: 34 Answers ...
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How do you write tests for the argparse portion of a python module? [closed]

...th parameter args=sys.argv[1:]. It already calls the ArgumentParser.parse_known_args-method. With argument args==None it will obtain them with args = _sys.argv[1:] where _sys is an alias for sys. (It might be an update since the answer was posted.) – Thomas Fauskanger ...
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How well is Unicode supported in C++11?

...le to focus on an encoding that was superseded over 20 years ago, I don't know‡. It's not like support for more encodings is bad or anything, but UCS-2 shows up too often here. I would say that char16_t is obviously meant for storing UTF-16 code units. However, this is one part of the s...
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What optimizations can GHC be expected to perform reliably?

GHC has a lot of optimizations that it can perform, but I don't know what they all are, nor how likely they are to be performed and under what circumstances. ...
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Reset Entity-Framework Migrations

...ked up my migrations, I used IgnoreChanges on the initial migration, but now I want to delete all my migrations and start with an initial migration with all of the logic. ...