195

Object Oriented Perl-gramming
SubClasses

  • A sub-class needs an object constructor method which is simply a subroutine which returns a reference to its parent-class instance

  • A sub-class may also contain methods which either override or inherit functionality from methods of its parent class 
      package MySubClass;

@ISA = qw( MyClass );

sub new {
	my $type = shift;           # Get the package/type name
	my $self = MyClass->new;    # Reference to parent's hash
	return bless $self, $type;  # Add and return the class instance
}

sub MyMethod {
	my $self = shift;
	$self->SUPER::MyMethod();  # Call the parent method if desired
	print "   MySubClass::MyMethod called!\n";
}

  • A class constructor and methods can then be called

      $myObject = MySubClass->new();
      $myObject->MyMethod();