C++ template typedef
I have a class
template<size_t N, size_t M>
class Matrix {
// ....
};
I want to make a typedef
which creates a Vector
(column vector) which is equivalent to a Matrix
with sizes N and 1. Something like that:
typedef Matrix<N,1> Vector<N>;
Which produces compile error. The following creates something similar, but not exactly what I want:
template <size_t N>
class Vector: public Matrix<N,1>
{ };
Is there a solution or a not too expensive workaround / best-practice for it?
C++11 added alias declarations, which are generalization of typedef
, allowing templates:
template <size_t N>
using Vector = Matrix<N, 1>;
The type Vector<3>
is equivalent to Matrix<3, 1>
.
In C++03, the closest approximation was:
template <size_t N>
struct Vector
{
typedef Matrix<N, 1> type;
};
Here, the type Vector<3>::type
is equivalent to Matrix<3, 1>
.