“ return * this”赋值运算符重载

Question

Fraction& Fraction::operator= (const Fraction &fraction)
{
    // do the copy
    m_numerator = fraction.m_numerator;
    m_denominator = fraction.m_denominator;

    return *this;
}

int main()
{
    Fraction fiveThirds(5, 3);
    Fraction f;
    f = fiveThirds; // calls overloaded assignment
    std::cout << f;

    return 0;
}

I have some problems with the concept of return this when overloading the assignment operator.

In the main function f = fiveThirds will call the assignment operator, and it will return *this , ie return a Fraction object!

The problem is f = fiveThirds will return the object, but there isn't any Fraction object to receive it!

In the assignment chain x=y=z , y=z will return an object ( k ) which will be assigned to x , however x=k will also return an object, so who receives this object?

I've done my best to describe my problem.

Answer 1

The problem is f = fiveThirds will return the object, but there isn't any Fraction object to receive it!

More accurately, it returns a reference to an object.

so who receives this object?

The return value is discarded.

There is no problem.