Infinite recursion in move-assignment operator of `Mem`

Unless I'm seeing things incorrectly, the following snippet should be infinite recursion:

Lines 67 to 70 in a0a7b02

    
           Mem &operator=(Mem &&other) { 
        
               *this = std::move(other); 
        
               return *this; 
        
           }

Furthermore, the move constructor and move assignment operator should be noexcept.

	Mem &operator=(Mem &&other) {
	*this = std::move(other);
	return *this;
	}