c++ - Templated Fixed + Variable-Sized Class -

let's have several container classes these:

template<typename t> class container {     /* ... */ };  template<typename t, size_t> class array : public container<t> {     /* fixed-sized container */ };  template<typename t> class vector : public container<t> {     /* variable-sized container */ }; 

and have class accepts 1 of these template parameter:

template<typename t, template<typename> class u, size_t m> class polygon {     u<t> vertices; // problem, if user passes array (it needs 2 parameters)     u<t, m> vertices; // problem, if user wants use variable-sized container (it needs 1 parameter) }; 

my question is, can somehow (probably through tricky template parameter magic) make consuming class accept type of container (fixed or variable-sized, differing template signatures)?

the guarantees template signatures are, if fixed-sized container have 2 parameters <type, size> , 1 if variable-sized container <type>

it's way less tricky think is. can template on container itself:

template <class container> class polygon {     container vertices; }; 

this work meets container requirements, fixed sized or not.

the problem of choosing right template arguments container gets moved instantiation point parameters , types must known anyways.