Why doesn't C++ have a const universal reference?
c++, c++11, universal-reference
Solution
What would a const universal reference be? It would be a reference that can not be modified. And moving from an rvalue-reference is a modification. Therefore, if there is such a thing as a const universal reference, it is simply `const T&`.
Problem
Scott Meyers says (for parameters to function templates): Universal references can only occur in the form "`T&&`"! Even the simple addition of a `const` qualifier is enough to disable the interpretation of "`&&`" as a universal reference. Why doesn't C++ have a `const` universal reference? Any technical reason?