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C++ template typedef

Submitted by: @import:stackoverflow-api·Mar 10, 2026·

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Problem

I have a class

template
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 Vector;

Which produces compile error. The following creates something similar, but not exactly what I want:

template 
class Vector: public Matrix
{ };

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 
using Vector = Matrix;

The type Vector is equivalent to Matrix.

In C++03, the closest approximation was:

template 
struct Vector
{
    typedef Matrix type;
};

Here, the type Vector::type is equivalent to Matrix.

template <size_t N>
using Vector = Matrix<N, 1>;

template <size_t N>
struct Vector
{
    typedef Matrix<N, 1> type;
};

Stack Overflow Q#2795023, score: 686

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