> 
> **Possible Duplicate:**  
> 
> [C++ invoke explicit template constructor](https://stackoverflow.com/questions/2786946/c-invoke-explicit-template-constructor) 
> 
> 
> 

Hi,

```
template <typename T>
class testing
{
public:

    template <typename R>
    testing()
    {
       // constructor A
    }

    template <typename R>
    testing(const R&)
    {
       // constructor B
    }
};

```

What is the syntax to invoke the constructor A?

I will need the type to be passed during the constructor call. Is there a way to call it? constructor B is a workaround as I only need to know the type not the whole object.

Thanks,

Stephen