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Volatile boolean vs AtomicBoolean

...ranteed that every method is "atomic". Thus, if you use an AtomicInteger and getAndAdd(int delta), you can be sure that the result will be 10. In the same way, if two threads both negate a boolean variable concurrently, with an AtomicBoolean you can be sure it has the original value afterwards, wi...
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What's the absurd function in Data.Void useful for?

...pe is involved in the return type of a function. absurd arises when we're converting between these two representations. For example, callcc :: ((a -> m b) -> m a) -> m a uses (implicit) forall b. It could be as well of type ((a -> m Void) -> m a) -> m a, because a call to the c...
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How come a non-const reference cannot bind to a temporary object?

...ct, which function getx() returns? Clearly, this is prohibited by C++ Standard but I am interested in the purpose of such restriction, not a reference to the standard. ...
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Why use multiple columns as primary keys (composite primary key)

... Your understanding is correct. You would do this in many cases. One example is in a relationship like OrderHeader and OrderDetail. The PK in OrderHeader might be OrderNumber. The PK in OrderDetail might be OrderNumber AND LineNumber. ...
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What is the best way to check for Internet connectivity using .NET?

What is the fastest and most efficient way to check for Internet connectivity in .NET? 27 Answers ...
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How to remove item from list in C#?

...s { public int ID; public string FirstName; public string LastName; } and assigned some values to results as follows: var results=new List<myClass> { new myClass() { ID=1, FirstName="Bill", LastName="Smith" }, new myClass() { ID=2, FirstName="John", LastName="Wilson" }, new ...
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Prefer composition over inheritance?

...this case, it makes sense to extract it out as an interface / class / both and make it a member of both classes. Update: Just came back to my answer and it seems now that it is incomplete without a specific mention of Barbara Liskov's Liskov Substitution Principle as a test for 'Should I be inher...
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What is an optional value in Swift?

...long with Generics) are one of the most difficult Swift concepts to understand. Because of how they are written and used, it's easy to get a wrong idea of what they are. Compare the optional above to creating a normal String: var name: String = "Bertie" // No "?" after String From the syntax it loo...
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How to hide first section header in UITableView (grouped style)

...the result is that drawings are no longer aligned to pixels, causing blurs and reducing performance. Just try it in the simulator: it has an option to highlight problematic alignment. – Codo Nov 1 '13 at 17:02 ...
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Easy way to write contents of a Java InputStream to an OutputStream

... but I suspect I'm just missing something which would make my life easier (and the code clearer). 23 Answers ...