#  InstanceTests.py  Copyright (c) Kari Laitinen

#  http://www.naturalprogramming.com

#  2006-05-29  File created.
#  2022-12-27  Converted to Python 3.

#  Testing built-in functions isinstance()  and  issubclass()
#  Note that the second parameter (argument) for these functions may
#  be a tuple.


from Date import Date

class  TestClass :

   def __init__( self ) :

      print( "\n TestClass constructor executed."  )


class DerivedClass ( TestClass ) :

   pass

#  The main program begins.

some_test_object  =  TestClass()

some_derived_class_object  =  DerivedClass()

print( "\n  isinstance( some_test_object, Testclass )       returns     %s"  \
       % isinstance( some_test_object, TestClass ) )
print( "\n  isinstance( some_derived_class_object, TestClass ) returns  %s"  \
       % isinstance( some_derived_class_object, TestClass ) )
print( "\n  isinstance( some_test_object, DerivedClass )    returns     %s"  \
       % isinstance( some_test_object, DerivedClass ) )
print( "\n  isinstance( some_test_object, ( DerivedClass, TestClass ) ) returns    %s"  \
       % isinstance( some_test_object, ( DerivedClass, TestClass ) ) )
print( "\n  isinstance( some_test_object, ( Date, str ) )   returns   %s"  \
       % isinstance( some_test_object, ( Date, str) ) )
print( "\n  issubclass( DerivedClass, TestClass )           returns   %s"  \
       % issubclass( DerivedClass, TestClass ) )
print( "\n  issubclass( DerivedClass, ( Date, str ) )       returns   %s"  \
       % issubclass( DerivedClass, ( Date, str ) ) )
print( "\n  issubclass( DerivedClass, ( Date, TestClass ) ) returns   %s"  \
       % issubclass( DerivedClass, ( Date, TestClass ) ) )

#  The last statement prints True because one class given in the tuple
#  is a base class of DerivedClass