Problems with D const ref vs C++ const &

[Craig Black]

In C++ I could to the following:

Vector3 cross(const Vector3 &a, const Vector3 &b) { ... }

and then call it like this:

Vector3 a, b, c;
a = cross(b, c);
a = cross(b-a, c-a);

But in D I have to define two functions if I want pass by reference to work:

Vector3 cross(ref const Vector3 a, ref const Vector3 b) {...}
Vector3 cross(Vector3 a, Vector3 b) {...}

Not having an l-value forces me to pass by value, and I have to define two 
functions.  I know about auto ref but that only works for templates, and the 
compiler generates two functions which could lead to code bloat if the 
function is a big one.

-Craig