C++ template typedef

Question

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?

Answer 1

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>.

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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>.