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Should switch statements always contain a default clause?

...akes appropriate action for unhandled values, in case an invalid value was cast to the enum type. So this may work best for simple cases where you can return within the enum case rather than break. enum SomeEnum { ENUM_1, ENUM_2, // More ENUM values may be added in future }; int foo(So...
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java: Class.isInstance vs Class.isAssignableFrom

...n instance. It returns true when the parameter obj is non-null and can be cast to MyClass without raising a ClassCastException. In other words, obj is an instance of MyClass or its subclasses. MyClass.class.isAssignableFrom(Other.class) will return true if MyClass is the same as, or a superclass ...
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Why shouldn't Java enum literals be able to have generic type parameters?

... information for type-checks. And then "converts" the generic type to type casts. I'll rephrase the question – Lukas Eder Nov 27 '10 at 9:32 ...
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Is it possible to do start iterating from an element other than the first using foreach?

...DataGridView, try this foreach (DataGridViewRow row in dataGridView1.Rows.Cast<DataGridViewRow().Skip(3)) If you want to copy contents of one DataGridView to another skipping rows, try this, foreach (DataGridViewRow row in dataGridView1.Rows.Cast<DataGridViewRow>().Skip(3)) { foreac...
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Why don't Java Generics support primitive types?

...entirely compile-time construct - the compiler turns all generic uses into casts to the right type. This is to maintain backwards compatibility with previous JVM runtimes. This: List<ClassA> list = new ArrayList<ClassA>(); list.add(new ClassA()); ClassA a = list.get(0); gets turned i...
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Move capture in lambda

...t;type_traits> #include <functional> namespace detail { enum selection_enabler { enabled }; } #define ENABLE_IF(...) std::enable_if_t<(__VA_ARGS__), ::detail::selection_enabler> \ = ::detail::enabled // This allows forwarding an object using the copy c...
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Reference — What does this symbol mean in PHP?

... only for integers. It doesn't work for non-integer numbers, because usort casts your comparator function's return values to int, which means 0.5 gets cast to 0, which means that two numbers with a difference of less than 1, such as 4 and 4.6, may (depending upon which one gets passed as the first a...
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How to update PATH variable permanently from Windows command line?

...rentControlSet\Control\Session Manager\Environment registry key, then broadcast a WM_SETTINGCHANGE message with lParam set to the string "Environment". This allows applications, such as the shell, to pick up your updates. Note that your application will need elevated admin rights in order to be ab...
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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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Using multiple let-as within a if-statement in Swift

...'m unwrapping two values from a dictionary and before using them I have to cast them and test for the right type. This is what I came up with: ...