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Idiom #271 Test for type extension

If a variable x passed to procedure tst is of type foo, print "Same type." If it is of a type that extends foo, print "Extends type." If it is neither, print "Not related."

public static void tst(Object x) {
  if (x.GetType() == typeof(foo))
    Console.WriteLine("Same type.");
  else if (x.GetType().IsAssignableTo(typeof(foo)))
    Console.WriteLine("Extends type.");
  else
    Console.WriteLine("Not related.");			
}
#include <iostream>
#include <type_traits>
template<typename T>
void tst(T)
{
    using namespace std;

    // Strip away any references and pointer
    typedef remove_const<remove_pointer<decay<T>::type>::type>::type D;

    if(is_same<D, foo>::value)
    {
        cout << "same type" << endl;
    }
    else if(is_base_of<foo, D>::value)
    {
        cout << "extends type" << endl;
    }
    else
    {
        cout << "not related" << endl;
    }
}
tst(x) {
  if (x.runtimeType == Foo) {
    print("Same Type.");
  } else if (x is Foo) {
    print("Extends type.");
  } else {
    print("Not related.");
  }
}
  subroutine tst (x)
    class (*), intent(in) :: x
    type (foo) :: y
    if (same_type_as (x,y)) then
       write (*,'(A)') "Same type."
    else if (extends_type_of (x,y)) then
       write (*,'(A)') "Extends type."
    else
       write (*,'(A)') "Not related."
    end if
  end subroutine tst
uses classes;
procedure tst(x: tobject);
begin
  if x.ClassType = foo then
    writeln('Same type')
  else if x is foo then
    writeln('Extends type')
  else
    writeln('Not related');
end; 
def tst(x):
    if isinstance(x, foo):
        print("Same type.")
    elif issubclass(type(x), foo):
        print("Extends type.")
    else:
        print("Not related.")

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tkoenig