Multiple return values in C++ [closed] - c++

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So, before quite some exposition, here comes my question:
Why is there no support for multiple return variables/values in C++ (yet)?
To give you some more notes:
What (if any) is conceptually a problem with multiple return values and c++?
Is there something in the way the compiler implements returing a values from a function which makes multiple return values impossible/inefficient?
Having worked a lot with lua recently I've come to ask myself why C++ does not permit to return multiple values/variables from a function. To illustrate, let me give you a lua example:
-- get the first four values of the fibonacci sequence
local function fib4()
return 1, 1, 2, 3
local fib0, fib1, fib2, fib3 = fib4()
Being able to return multiple variables/values at once is a very useful feature indeed, which I typically emulate in the C++ world by creating structs (essentially collecting the variables in a wrapper) which are returned by the function in question. If one uses this approach a lot, the soure files will be cluttered with structs each containing some variables; none of these struct needs to be an actual object (and is implemented as a complete object). In a way the conceptual problem is somewhat similar the one resulting from using structs for creating functors [instead of lambdas]:
It destroys locality
It introduces objects which are not conceptually objects but rather a helper
On the pro side it increases code readability:
struct point_three_dim_t {
double x;
double y;
double z;
};
point_three_dim_t point = getCollisionPoint();
However, a priori you don't know whether the members representing the coordinates are named x, y and z or first, second and third. So again, you have to check how point_three_dim_t was defined. This would not be the case if
double x, y, z = getCollisionPoint();
were correct syntax.
Using C++11 we can achieve conceptually the same by using either std::tuple or std::tie
std::tuple<double,double,double> getCollisionPoint();
// Using std::tie
double x, y, z;
std::tie( x, y, z ) = getCollisionPoint();
// Using std::tuple
std::tuple<double,double,double> point = getCollisionPoint();
This gets us much closer to clean and local code, however, I think neither syntax is quite as appealing as the one I'm used from scripting languages like lua.