c++ - How to create a template class with a template container of different objects as a parameter -

how can declare template class (a library of components) take vector containing components parameter? here stripped down version of code example:

    // in library.h     using namespace std;      template<typename t,         template <typename, typename = std:allocator<t>> class container>     class library {         container<t> comp_lib;         library(container<t> &vc) {comp_lib = vc}     };      // in mainprogram.cpp     #include "library.h"     // other includes...     using namespace std;      int main() {     library<int, vector> intlib;     return(0);     } 

as mentioned before meant library of components. instead of holding vectors containing integers library template meant hold vectors containing general components, vectors containing resistors, vectors containing capacitors , vectors containing inductors. resistors, capacitors , inductors derived classes component base class.

when run code, not compile , receive these error messages:

c2079: 'intlib' uses undefined class 'library' on line [ library intlib ] in mainprogram.cpp

c3855 'library': template parameter 'c' incompatible declaration on line [ }; ] in library.h (the last line)

c3855 'library': template parameter 'vector' incompatible declaration on line [ }; ] in library.h (also, last line)

i've looked @ lots of different articles concerning template template parameters, answer has been useful far although doesn't seem solve problem i'm having: template class template container

the desired result able write statements such as:

      library<resistor, vector<resistor>> resistor_lib;       library<capacitor, vector<capacitor>> capacitor_lib;       library<inductor, vector<inductor>> inductor_lib;       library<component, vector<component>> component_lib; 

in main using same template.

thanks, appreciated

you need template the container , let tell stored type. standard containers means of value_type definition. like:

template <typename tcontainer> class library { private:      tcontainer container_;  public:      using container_type = tcontainer;     using value_type = typename tcontainer::value_type;      library(const container_type &initvalues) {         std::copy(initvalues.begin(), initvalues.end(),             std::back_inserter(container_));     }      [...] }; 

this should work vector, list , can "back_inserted". additionally can reference container , object types means of container_type , value_type.

instances declared like

library<std::vector<int> > lib(someinitializer);