One of the biggest advantages of using C++ is templates. Templates were designed from the ground up to allow developers to write one function to handle many different types of parameters. In this article, Mitchell will explain what both function and class templates are, and give examples of each.
The Mighty C++ Template - Instantiating the class (Page 7 of 9 )
Before we can use our class template, we must create an instance of it within our main function:
MyClass<int> mc(1, 2, 3);
cout << "Return value is: " << mc.GetAverage() << endl << endl;
On the first line, we are creating a new instantiation of our class template. Between the angled brackets, we are telling the C++ compiler that our class will be handling integer (int) type variables. This is a mandatory inclusion and the compiler will complain if you leave it out. The new instantiation of our “MyClass” template is called “mc”. We are passing three values to the default constructor, which will be stored as the private variables n1, n2 and n3. In our examples, these variables will be of type int, meaning T will take on the role of an integer.
On the second line above, we simply call the GetAverage() function of our class template, just like we would with any class, outputting the value returned from the function, which looks something like this: