CODEWITHSUNDEEP
c++c++11vectormove-semantics
user456
user456

Reputation: 11

How can I use Move constructor instead of Move assignment operator in my own class Vector?

I have my own class Vector which implements Move constructor, Move assignment operator and method push_back for rvalue

template<typename T>
class Vector
{
private:
    T* buffer;
    size_t size;
    size_t capacity;
public:
    Vector(size_t s) {
        size = 0;
        capacity = s;       
        buffer = new T[capacity];
    }
    //Move constructor
    Vector(Vector&& tmp): buffer(tmp.buffer),
                          size(tmp.size),
                          capacity(tmp.capacity)
    {
        tmp.buffer = nullptr;
    }
    //Move assignment operator
    Vector& operator=(Vector&& tmp) {
        size = tmp.size;
        capacity = tmp.capacity;
        buffer = std::move(tmp.buffer);
        tmp.buffer = nullptr;
        return *this;
    }
    void push_back(const Vector<T>& v) {
        if (size >= capacity)
            reserve(capacity + 5);
        buffer[size++] = v;
    }
    //push_back for rvalue
    void push_back(T&& v) {
        if (size >= capacity)
            reserve(capacity + 5);
        buffer[size++] = std::move(v);
    }
    ~Vector() {
        delete[] buffer;
    }

In method push_back(T&& v) the line 

buffer[size++] = std::move(v);

uses Move assignment operator. How can I change code so that it will use Move constructror ?

Upvotes: 1

Views: 340

Answers (2)

Sergey Slepov
Sergey Slepov

Reputation: 2121

Use placement new:

new (&buffer[size++]) T (std::move(v));

Here is a complete example: http://cpp.sh/6s4i3

Upvotes: 3

Anil Degirmenci
Anil Degirmenci

Reputation: 31

i was moving ball but if there is something usefull for you

#pragma once
class movement
{
private:
Ball *b;
int size;

public:
movement(void)
{
    size=0;
}
Ball getBall(int i)
{
    return b[i];
}
void insertBall(Ball n)
{
    Ball *temp=new Ball[size+1];
    for (int i = 0;i<size; i++)
    {
        temp[i]=b[i];
    }
    temp[size]=n;
    delete []b;
    b=temp;
    size++;
}
void update(Ball food,Ball b)
{
    for (int i = 0; i < size; i++)
    {
        //if ((b->getPoint().getX() == b->getPoint().getY())
        if (food.getPoint().getX == b.getPoint().getX() && food.getPoint().getY == b.getPoint().getY())
        {
            insertBall(b);
        }

    }
}

};

Upvotes: 0

Related Questions