I would say that requiring this to make the program ill-formed (that is, make this a compilation error) would complicate the standard considerably for little benefit. You’d have to exactly spell out in the standard when such cases shall be diagnosed, and all compilers would have to implement them. If you specify too little, it … Read more
You’re probably returning an object that’s on the stack. That is, return_Object() probably looks like this: Object& return_Object() { Object object_to_return; // … do stuff … return object_to_return; } If this is what you’re doing, you’re out of luck – object_to_return has gone out of scope and been destructed at the end of return_Object, so … Read more
There is no difference unless you write something weird like (v1 += v2) = v3; In the first case, the assignment will be to a temporary, and the overall effect will be v1 += v2. In the second case, the assignment will be to v1, so the overall effect will be v1 = v3. In … Read more
The explanation is assuming that there is some reasonable implementation for foo which returns an lvalue reference to a valid int. Such an implementation might be: int a = 2; //global variable, lives until program termination int& foo() { return a; } Now, since foo returns an lvalue reference, we can assign something to the … Read more