How to use templates propperly

[nomad5000]

Helo I´m having trouble finding out how to use templates properly. Te problem I´m having is, that I can´t find the right way to make the templates work outside the file where the class using the template is declared. Look at the following example.

Template.h file
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#ifndef TEMPLATE_H
#define TEMPLATE_H

template<typena me T>
class Template{
private:
T info;
public:
Template(T info);
T getInfo()const;
void setInfo(T info);
};

#endif
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Template.cpp file
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#include "Template.h "

template<typena me T>
Template<T>::Te mplate(T info){
this->info = info;
}

template<typena me T>
T Template<T>::ge tInfo()const{
return this->info;
}

template<typena me T>
void Template<T>::se tInfo(T info){
this->info = info;
}
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#include <iostream>
#include "Template.h "
using namespace std;
int main(){
Template< int > t(1);
cout<<t.getInfo ()<<endl;
}
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the error message the compiler tells me is the following:
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Error: Unresolved external 'Template<int>: :Template<int>( int)' referenced from C:\DOCUMENTS AND SETTINGS\MICHAE L SCHMIDT\CBPROJE CT\TEMPLATE\WIN DOWS\DEBUG_BUIL D\MAIN.OBJ

Error: Unresolved external 'Template<int>: :getInfo() const' referenced from C:\DOCUMENTS AND SETTINGS\MICHAE L SCHMIDT\CBPROJE CT\TEMPLATE\WIN DOWS\DEBUG_BUIL D\MAIN.OBJ
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Any help will be greatly apreciated!

Michael

[horace1]

the problem is with template instantiation where you have to generate an explict definition of a class from a template, see
http://www.is.pku.edu. cn/~qzy/cpp/vc-stl/templates.htm

for example the following template.cpp works with your main() with the gcc compiler

#include "Template.h"

template<typename T>

Template<T>::Template(T info){

  this->info = info;

}



template<typename T>

T Template<T>::getInfo()const{

  return this->info;

}



template<typename T>

void Template<T>::setInfo(T info){

  this->info = info;

} 

template class Template<int>;  // explicit instantiation of int version

[nomad5000]

this is verry nice and I already knew about it, but there has to be a way where you dont have to use this
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template class Template<int>;// explicit instantiation of int version
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What I want to do is write a Class for example a Stack class that I can use with whatever type of data without having to explicitly instantiate.

[horace1]

this is verry nice and I already knew about it, but there has to be a way where you dont have to use this
[HTML]
template class Template<int>;// explicit instantiation of int version
[/HTML]
What I want to do is write a Class for example a Stack class that I can use with whatever type of data without having to explicitly instantiate.

a template has to be instantiated for a particular type at some point - how you do it can depend on the compiler - I gave the example using gcc which I mainly use. What compiler are you using? if you do a google search on template instantiation you will find plenty of discussions!

[nomad5000]

I'm using Borland Win 32 compiler tools
probably the problem is, that mycompiler doesn't suport automatic template instanciation. Something that I find verry anoing. What point does it have to use templates if you cant use them for a type without instancieting them first.

Thank you for your help!

regards
Michael