If T doesn’t have trivial destructor, then for usual compiler implementations, new T[1] has an overhead compared to new T. The array version will allocate a little bit larger memory area, to store the number of elements, so at delete[], it knows how many destructors must be called. So, it has an overhead: a little … Read more
operator delete is unique in being a non-member or static member function that is dynamically dispatched. A type with a virtual destructor performs the call to its own delete from the most derived destructor. struct abc { virtual ~abc() = 0; }; struct d : abc { operator delete() { std::cout << “goodbye\n”; } }; … Read more
Just do: MyClass::MyClass(int m_size) : size(m_size), vec(m_size, 0) You already seem to know about initializer lists, why not initialize vector there directly? vec = new vector<int>(size,0); is illegal because new returns a pointer and in your case vec is an object. Your second option: vector<int> temp(size,0); vec = temp; although it compiles, does extra work … Read more
You cannot override variables in C#, but you can override properties: public class Item { public virtual string Name {get; protected set;} } public class Subitem : Item { public override string Name {get; protected set;} } Another approach would be to change the value in the subclass, like this: public class Item { public … Read more
This expression: CPlayer(position, attacker) creates a temporary object of type CPlayer using the above constructor, then: CPlayer newPlayer =…; The mentioned temporary object gets copied using the copy constructor to newPlayer. A better way is to write the following to avoid temporaries: CPlayer newPlayer(position, attacker);
It will call delete[] and hence the entire array will be reclaimed but I believe you need to indicate that you are using an array form of unique_ptrby: std::unique_ptr<int[]> my_array(new int[5]); This is called as Partial Specialization of the unique_ptr.
static void Main() { int A = new int(); int B = default(int); int C = 100; Console.Read(); } Is compiled to .method private hidebysig static void Main() cil managed { .entrypoint // Code size 15 (0xf) .maxstack 1 .locals init ([0] int32 A, [1] int32 B, [2] int32 C) IL_0000: nop IL_0001: ldc.i4.0 IL_0002: … Read more
There’s no new/delete expression in C. The closest equivalent are the malloc and free functions, if you ignore the constructors/destructors and type safety. #include <stdlib.h> int* p = malloc(sizeof(*p)); // int* p = new int; … free(p); // delete p; int* a = malloc(12*sizeof(*a)); // int* a = new int[12]; … free(a); // delete[] a;
Every use of new should be balanced by a delete, and every use of new[] should be balanced by delete[]. for(int i=0;i<N;i++) delete array[i]; delete[] array; That would be appropriate only if you initialized the array as: Objects **array = new Objects*[N]; for (int i = 0; i < N; i++) { array[i] = new … Read more
If construction of any object in the buffer throws an exception, the previously constructed objects must be destructed. That requires an available destructor.