• wondermail szm.sk (25/25) Oct 10 2004 Hi there,

wondermail szm.sk writes:

Hi there,
I've just read the spec - great D, but can I somehow do the "type promotion"
e.g. for matrices

class CMatrix(T, int M, int N)
{
T data[M][N];
}

CMatrix!(float,3,3) mf;
CMatrix!(double,3,3) md;

mf + md; // float matrix + double matrix = double matrix

// or

CMatrix!(float,1,3) v3;
CMatrix!(float,3,3) m33;

v3 * m33; // and this is really necessary to me


-----------
In C++ I did something like this:

template <class X, class Y> TAdd {};

template <> TAdd<float,double> { typedef double RET; }; // float + double =
double

template <class X, class Y, int M, int N> CMatrix<typename TAdd<X,Y>::RET,M,N>
operator + (CMatrix<T,M,N> const &a, CMatrix<T,M,N> const &b) { /*...*/ }

thanks Juraj Onderik
(as I understand templates in D now - it's not really superset of C++ templates,
or is it? :)

Juraj Onderik