int &b = ++a; // this line works fine int &c = a++; // results in error

Question

int main()
{
  int a = 10;
  int &b = ++a; // this line works fine
  int &c = a++; // results in error
}

can someone please explain me reason for this

Have a look at [this](https://stackoverflow.com/questions/32560823/post-increment-in-assignment-to-reference-c) — Wander3r, Dec 13 '19 at 06:04
use `int&& c = a++;` . You must match lvalue reference to lvalue expressions etc. — M.M, Dec 13 '19 at 07:32

score 1 · Answer 1 · answered Dec 13 '19 at 05:58

1

int &c = a++;

You get the error because a++ results in rvalue expression whose reference you cannot take.

answered Dec 13 '19 at 05:58

kiran Biradar

Markus Mayr · Answer 2 · 2019-12-13T07:41:54.947

0

In non-technical terms, it is forbidden, to take a (non-const) reference to a temporary.

The expression ++a does not generate a temporary. It modifies itself and returns a reference to itself.

The expression a++ on the other hand, creates a copy of itself, then modifies itself, then returns the copy. That copy is a temporary.

edited Dec 13 '19 at 07:41

answered Dec 13 '19 at 07:36

Markus Mayr

2 Answers2