Move-assignment and reference member
c++, c++11, move-semantics
Solution
(Posted as an answer from comment as suggested by the OP)
In general if one wants to do non-trivial stuff with references in C++, one would be using `reference_wrapper<T>`, which is essentially a fancy value-semantic stand-in for a `T&`, then one would be done with it - it already provides (re)assignment and other operations. I'm sure that would make move constructor and assignment near-trivial, if not trivial (note not `trivial` as in per the `is_trivially_*` semantics).
"Reference wrapper" is added to C++03 as part of TR1, and is part of C++11.
Documentation: http://en.cppreference.com/w/cpp/utility/functional/reference_wrapper
Problem
Copy-assignment for a class with a reference member variable is a no-no because you can't reassign the reference. But what about move-assignment? I tried simply `move`ing it but, of course, that destroys the source object when I just want to move the reference itself: ``` class C { public: C(X& x) : x_(x) {} C(C&& other) : x_(std::move(other.x_)) {} C& operator=(C&& other) { x_ = std::move(other.x_); } private: X& x_; }; X y; C c1(y); X z; C c2(z); c2 = c1; // destroys y as well as z ``` Should I just not be implementing move-assignment and sticking with move-construction only? That makes `swap(C&, C&)` hard to implement.