Strange "Undefined reference" error on C++ Netbeans project -

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• why can templates implemented in header file? 13 answers

the solution duplicate question did not work

i have following files:

listaenc.hpp

#include "elemento.hpp"  template<typename t> class listaenc {  public:     listaenc();     ~listaenc(); //  inicio     void adicionanoinicio(const t& dado);     t retiradoinicio();     void eliminadoinicio();         t pegarhead(); //  posicao     void adicionanaposicao(const t& dado, int pos);     int posicao(const t& dado) const;     t* posicaomem(const t& dado) const;     bool contem(const t& dado);     t retiradaposicao(int pos); //  fim     void adiciona(const t& dado);     t retira(); //  especifico     t retiraespecifico(const t& dado);     void adicionaemordem(const t& data); //  outras     bool listavazia() const;     bool igual(t dado1, t dado2);     bool maior(t dado1, t dado2);     bool menor(t dado1, t dado2);     void destroilista();         int pegartamanholista();  private: //trocar pra private     elemento<t>* head;     int size; }; 

listaenc.cpp

#include "listaenc.hpp" #include <cstdlib> #include <iostream>  template<typename t> listaenc<t>::listaenc() {      ... } 

main.cpp

#include "listaenc.hpp" using namespace std; int main(int argc, char** argv) {     double x1, y1;      x1 = 2; y1 = 4.2;      listaenc<int>* teste = new listaenc<int>();      return 0; } 

this should compile fine, undefined reference error listaenc on main.cpp. have more files in reference listaenc undefined, tried isolating , still can't work. understand why happening?

edit: more specifically, there undefined error constructor , destructor of listaenc

you can't separate declaration implementation when instantiate template class. combine code single file , include in main.cpp.

or, go step further , implement functions inline in class declaration if suits coding style.