RaGa__M questions

• why rvalue can't assign to constexpr reference variable
• How the when<> trait in boost.Hana works?
• why std::move takes forward_reference instead of lvaue reference [duplicate]
• Does Making std::mutex as static creates race-condition for the mutex itself
• Const qualifier and forward reference
• What to call the expression `T (&some(...)) [2]` where T=char
• Empty class size in python
• Is __del__ really a destructor?
• Why does destructor disable generation of implicit move methods?
• Why adding `const` makes the universal reference as rvalue

RaGa__M answers