Copy construction vs assignment operator

[pabloist]

On Wikipedia, there's this sample code for a copy constructor:

If we write our own copy constructor that performs a deep copy then this problem goes away.

Array(const Array& copy)
  : size(copy.size), data(new int[copy.size]) 
{
    std::copy(copy.data, copy.data + copy.size, data);    // #include <algorithm> for std::copy
}

Here, we are creating a new int array and copying the contents to it.

However, since I've defined both a copy constructor and an assignment operator, would I need to copy the data from one object to another in the copy constructor?

// Copy constructor.
Array(const Array& toCopy)
: _rowSize(toCopy._rowSize),
  _colSize(toCopy._colSize)
{ _ptr = new T[_rowSize*_colSize]; }

template <typename T>
const Array<T>& Array<T>::operator=(const Array& rhs)
{
    // Prevent self assignment.
    if (&rhs != this)
    {
        if (_rowSize != rhs._rowSize ||
            _colSize != rhs._colSize)
        {
            delete[] _ptr;
            _rowSize = rhs._rowSize;
            _colSize = rhs._colSize;
            _ptr = new T[_rowSize*_colSize];
        }

        for (int i=0; i<_rowSize*_colSize; i++)
            _ptr[i] = rhs._ptr[i];
    }
    return *this;
}

Or should I add *this = toCopy; to my copy constructor? I'm sort of confused, haha.

[stereoMatching]

copy constructor and assignment are different concepts
copy constructor would only be called when you want to initiate an object

[pabloist]

So then would just adding *this = toCopy; within the copy constructor work?

[Disch]

Only if _rowSize, _colSize, and _ptr are properly initialized in the copy constructor (zero/null for all would work).