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Copy constructor versus Clone()
...will have to use it. List<T> aList = new List<T>(aFullListOfT.Select(t=t.Clone())
– DanO
Jan 13 '14 at 23:06
1
...
MIN and MAX in C
... macro from doing such potentially dangerous type promotions, a final type cast to the intended type was used.
Rationale
We want both parameters to the macro to be of the same type. If one of them is of a different type, the macro is no longer type safe, because an operator like ?: will yield impl...
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 ...
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...
What is an existential type?
...ely become opaque; perhaps the only thing you can still do with it is type-cast it to Object.
Summary:
===========================================================
| universally existentially
| quantified type quantified type
------------------...
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...
Why are function pointers and data pointers incompatible in C/C++?
...be converted back to the original function pointer type, using an explicit cast, without loss of information. Note: The ISO C standard does not require this, but it is required for POSIX conformance.
– Jonathan Leffler
Sep 11 '12 at 18:23
...
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...
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...
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...