Question

I have a function that is defined as follows:

template < class T> T doSomething(const T value, const T value2, const T value3)
{
   T temp = value;
       //Do stuff
   return temp ;
}

in my main, I go to call it as follows:

doSomething(12.0, 23.0f, 2.0f);

I get an error saying no matching function for call doSomething(double, float, float).

I tried to used const_cast but it didn’t seem to fix the issue. Any help would be appreciated.

Answer 1

Your function definition uses same type “T” for every of three arguments.
C++ is not able to deduct types in cases like this.

Please choose way to fix:

• Different types for every argument

    template<typename A, typename B, typename C>
    A doSomething(const A& value, const B& value2, const C& value3)
    {
        A temp = value;
        //Do stuff
        return temp ;
    }

• Explicit template argument on call:

    doSomething<int>(12.0, 23.0f, 2.0f);

• Explicit type cast for argument on call:

    doSomething(12.0, static_cast<double>(23.0f), static_cast<double>(2.0f));