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How to easily map c++ enums to strings

...xtra syntactic sugar, here's how to write a map_init class. The goal is to allow std::map<MyEnum, const char*> MyMap; map_init(MyMap) (eValue1, "A") (eValue2, "B") (eValue3, "C") ; The function template <typename T> map_init(T&) returns a map_init_helper<T>. map...
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How to use if - else structure in a batch file?

...stion about if - else structure in a batch file. Each command runs individually, but I couldn't use "if - else" blocks safely so these parts of my programme doesn't work. How can I do make these parts run? Thank you. ...
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Finding quaternion representing the rotation from one vector to another

... Be aware that this does not handle the case of parallel vectors (both in the same direction or pointing in opposite directions). crossproduct will not be valid in these cases, so you first need to check dot(v1, v2) > 0.999999 and dot(v1, v2) < -0.999999, respectively, ...
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Makefile, header dependencies

...vided by the gnu preprocessor are a bit confusing. However, the removal of all directories from the build target with -MM is documented and not a bug [gpp]: By default CPP takes the name of the main input file, deletes any directory components and any file suffix such as ‘.c’, and appends ...
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Is there a Python equivalent of the C# null-coalescing operator?

In C# there's a null-coalescing operator (written as ?? ) that allows for easy (short) null checking during assignment: ...
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Simple insecure two-way data “obfuscation”?

...e to figure out your keys by just assuming that you used this code as-is! All you have to do is change some of the numbers (must be <= 255) in the Key and Vector arrays (I left one invalid value in the Vector array to make sure you do this...). You can use https://www.random.org/bytes/ to gener...
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How can I check if a Perl array contains a particular value?

...For the record, this code still does iterate through the array. The map{} call simply makes that iteration very easy to type. – Kenny Wyland Mar 3 '12 at 23:09 3 ...
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How to write a large buffer into a binary file in C++, fast?

... Try the following, in order: Smaller buffer size. Writing ~2 MiB at a time might be a good start. On my last laptop, ~512 KiB was the sweet spot, but I haven't tested on my SSD yet. Note: I've noticed that very large buffers tend to decrease performance. ...
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What are the use cases of Graph-based Databases (http://neo4j.org/)? [closed]

...mport some of their own data and graft it on top of our model, it could usually be done on site by the sales rep. Flexibility also helped when we were designing a new feature, saving us from trying to squeeze new data into a rigid data model. Having a weird database let us build a lot of our other ...
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What is the difference between AF_INET and PF_INET in socket programming?

... to do is to use AF_INET in your struct sockaddr_in and PF_INET in your call to socket(). But practically speaking, you can use AF_INET everywhere. And, since that's what W. Richard Stevens does in his book, that's what I'll do here. ...