problems with new / delete

[verani]

Hello, i wrote such code.

template <typename T>
class CyclicalArray {
private:
	T* mem_ptr;
public:
CyclicalArray(size_t capacity, const T& default_value) {
		this->default_value = default_value;
		this->capacity = capacity;
		head_index = 0; 
		mem_ptr = ::new T[capacity]; //memory allocating
		for(T* p = mem_ptr; p < mem_ptr + capacity * sizeof(T); p += sizeof(T)) {
			::new (p) T (default_value); //initialization
		} 
	}
~CyclicalArray() {
	for(T* p = mem_ptr + sizeof(T); p < mem_ptr + capacity * sizeof(T); p += sizeof(T)) {
			p->~T();
		}
		delete[] mem_ptr;
	}

But such destructor doesn't work. How should i make this correct?

[Banfa]

If you really want to do you own memory allocation then:

Don't construct every member of the array twice. If you want your array members initialised from a supplied default then either allocate each one individually using the default or use the assignment operator to copy the default value into each T.

Don't destruct every member of your array twice. Just call delete[], it will automatically call all the destructors.

If you are happy to let someone else do the memory management then just use a vector instead of doing it yourself.