Can we reassign the reference in C++?

It seems as if I have actually succeeded in reassigning a reference. Is that true?

No, you haven't. You are actually reassigning the value, and you are not rebinding the reference.

In your example, when you do int &ri = i;, ri is bound to i for its lifetime. When you do ri = j;, you are simply assigning the value of j to ri. ri still remains a reference to i! And it results in the same outcome as if you had instead written i = j;

If you understand pointers well, then always think of the reference as an analogical interpretation of T* const where T is any type.


ri = j; // >>> Is this not reassigning the reference? <<<

No, ri is still a reference to i - you can prove this by printing &ri and &i and seeing they're the same address.

What you did is modify i through the reference ri. Print i after, and you'll see this.

Also, for comparison, if you create a const int &cri = i; it won't let you assign to that.


When you assign something to a reference you actually assign the value to the object the reference is bound to. So this:

ri=j;

has the same effect as

i = j;

would have because ri is bound to i. So any action on ri is executed on i.

Tags:

C++

Reference