c++ - How do I check my template class is of a specific classtype?

Question

In my template-ized function, I'm trying to check the type T is of a specific type. How would I do that?

p/s I knew the template specification way but I don't want to do that.

template<class T> int foo(T a) {
  // check if T of type, say, String?
}

Thanks!

Answer 1

Instead of checking for the type use specializations. Otherwise, don't use templates.

template<class T> int foo(T a) {
      // generic implementation
}
template<> int foo(SpecialType a) {
  // will be selected by compiler 
}

SpecialType x;
OtherType y;
foo(x); // calls second, specialized version
foo(y); // calls generic version