an error from template

Question

Here is my code:

// head file
class JsonResponse
{
public:
    template<typename T>
    void add(const string &, const T &);
};

template<typename T>
void JsonResponse::add(const string & name, const T & t)
{
    // do something
}

I compile it and get this error:
error C4430: missing type specifier - int assumed. Note: C++ does not support default-int

Can you help me? thanks a lot.

which line cause the error? are you using `using namespace std`? Because `string` is not prefixed. — UmNyobe, Jun 29 '15 at 09:51
@UmNyobe `void add(const string &, const T &);` and `void JsonResponse::add(const string &name, const T & t)` — Yves, Jun 29 '15 at 09:53

score 0 · Accepted Answer · answered Jun 29 '15 at 09:55

0

This is not a template error. you are using string, which is not resolved unless there is a using namespace std directive. You should be using std::string instead

answered Jun 29 '15 at 09:55

UmNyobe

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omg.... I was cheated by Visual Studio again..... Sometimes the color hint doesn't work.... thx a lot. – Yves Jun 29 '15 at 10:02

score 0 · Answer 2 · answered Jun 29 '15 at 09:57

Use template like this , it will work

#include <iostream>
#include <string>

using namespace std;

class JsonResponse
{
    public:
       template<typename T>
       void add(const string &, const T &);
};

template<typename T>
void JsonResponse::add(const string & name, const T & t)
{
    std::cout<<name<<std::endl;
    std::cout<<t<<std::endl;
}

int main(void)
{
    JsonResponse jsonDbl;
    jsonDbl.add("nitendra",3);
    return 0;
}

an error from template

2 Answers2