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What is the difference between Integer and int in Java?
...ence to an object of (class) type Integer, or to null.
Java automatically casts between the two; from Integer to int whenever the Integer object occurs as an argument to an int operator or is assigned to an int variable, or an int value is assigned to an Integer variable. This casting is called box...
What is the exact problem with multiple inheritance?
...g part of the problem, if one does not need to allow identity-preserving upcasts and downcasts among all of the types from which an instance is derived or for which it is substitutable. Given X:B; Y:B; and Z:X,Y; assume someZ is an instance of Z. With virtual inheritance, (B)(X)someZ and (B)(Y)som...
Python hashable dicts
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@smido: Thanks. I also found that you can just cast a literal, i.e. hashabledict({key_a: val_a, key_b: val_b, ...}).
– HelloGoodbye
Oct 9 '18 at 7:35
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How do I pass a unique_ptr argument to a constructor or a function?
...eter by value. std::move doesn't actually move anything; it's just a fancy cast. std::move(nextBase) returns a Base&& that is an r-value reference to nextBase. That's all it does.
Because Base::Base(std::unique_ptr<Base> n) takes its argument by value rather than by r-value reference,...
Can a class member function template be virtual?
...ember functions are resolved statically. That is, the
member function is selected statically (at compile-time) based on the
type of the pointer (or reference) to the object.
In contrast, virtual member functions are resolved dynamically (at
run-time). That is, the member function is selec...
How to unit test abstract classes: extend with stubs?
... Oh no.. another tenet I'm gong to have to rethink! Thanks (both sarcastically for now, and non-sarcastically for once I have assimilated it and feel like a better programmer)
– Martin Lyne
Mar 18 '13 at 10:12
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How can I ensure that a division of integers is always rounded up?
...ounded up if necessary. Is there a better way than this? There is a lot of casting going on. :-)
8 Answers
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Swift - which types to use? NSString or String
...wift type, as in str.bridgeToObjectiveC().length for example. You can also cast a String to an NSString by using str as NSString.
However, the necessity for these techniques to explicitly use the Foundation types, or at least some of them, may be obsolete in the future, since from what is stated in...
Why array implements IList?
... (and transitively, ICollection) simplified the Linq2Objects engine, since casting the IEnumerable to IList/ICollection would also work for arrays.
For example, a Count() ends up calling the Array.Length under-the-hood, since it's casted to ICollection and the array's implementation returns Length...
Implicit type conversion rules in C++ operators
I want to be better about knowing when I should cast. What are the implicit type conversion rules in C++ when adding, multiplying, etc. For example,
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