Документация
HTML CSS PHP PERL другое

Section 11.8.  The SUPER Way of Doing Things

 
Previous
Table of Contents
Next

11.8. The SUPER Way of Doing Things

By changing the Animal class to the SUPER class in that invocation, we get a search of all our superclasses (classes listed in @ISA) automatically:

{ package Animal;
  sub speak {
    my $class = shift;
    print "a $class goes ", $class->sound, "!\n";
  }
}
{ package Mouse;
  @ISA = qw(Animal);
  sub sound { 'squeak' }
  sub speak {
    my $class = shift;
    $class->SUPER::speak;
    print "[but you can barely hear it!]\n";
  }
}

Thus, SUPER::speak means to look in the current package's @ISA for speak, invoking the first one found if there's more than one. In this case, we look in the one and only base class, Animal, find Animal::speak, and pass it Mouse as its only parameter.


Previous
Table of Contents
Next
© 2000- NIV