{
  package Before;
  sub new {
    my ($sClass,$f) = @_;
    my $fBefore= sub { print "Special stuff for class $sClass\n";
                       goto &$f
                     };
    return bless($fBefore,$sClass);
  }
}

{
  package AlsoBefore;
  our @ISA=qw(Before);
}

my $f1=Before->new(sub {print "Hello world!\n"});
my $f2=Before->new(sub {print "Bonjour, le monde!\n"});
my $f3=Before->new(sub {print "Guten tag, die welt!\n"});
my $f4=AlsoBefore->new(sub {print "Boker tov, olam!\n"});

$f1->(); $f2->(); $f3->(); $f4->();