+-----------+      +-----------+
|     O-----+----->|   12345   |
+-----------+      +-----------+

##</code><code>##

+----------\       +----------\
|     a     >      |     b     >
+----------/       +----------/
      |                  |
+-----------+      +-----------+
|     O-----+----->|   12345   |
+-----------+      +-----------+

##</code><code>##

+----------\
|     b     >      +----------\
+----------/       |     a     >
      |            +----------/
+-----------+            |
|     O-----+----->+###########+
+-----------+      +"""""""""""+
                   |    Foo    |
+----------\       +-----------+
|     c     >      |    Bar    |
+----------/       +-----------+
      |            |    Baz    |
+-----------+      +-----------+
|     O-----+----->|    Qux    |
+-----------+      +-----------+

##</code><code>##

+----------\
|     a     >                      +-->+###########+
+----------/                       |   +"""""""""""+
      |                            |   |    Foo    |
+-----------+                      |   +-----------+
|     O-----+----->+###########+   |   |    Bar    |
+-----------+      +"""""""""""+   |   +-----------+
                   |     O-----+---+
                   +-----------+
                   |     O-----+------>+###########+
                   +-----------+       +"""""""""""+
                   |     O-----+---+   |    Baz    |
                   +-----------+   |   +-----------+
                                   |   |    Qux    |
                                   |   +-----------+
                                   |
                                   |
                                   +-->+###########+
                                       +"""""""""""+
                                       |    Baz    |
                                       +-----------+


##</code><code>##

+----------\
|     a     >                 +-->+###########+
+----------/                  |   +"""""""""""+
      |                       |   |    Foo    |
+#########################+   |   +-----------+
+"""""""""""""""""""""""""+   |   |    Bar    |
+-----------\ +-----------+   |   +-----------+
|    aaa     >|     O-----+---+
+-----------< +-----------+
|    bbb     >|     O-----+------>+###########+
+-----------< +-----------+       +"""""""""""+
|    ccc     >|     O-----+---+   |    Baz    |
+-----------/ +-----------+   |   +-----------+
                              |   |    Qux    |
                              |   +-----------+
                              |
                              |
                              +-->+###########+
                                  +"""""""""""+
                                  |    Baz    |
                                  +-----------+


##</code><code>##

        $aref = [123, 456, 789];

##</code><code>##

        $href = {NAME => 'Bernd', EMAIL => 'bdulfer@sybase.com'};

##</code><code>##

        $fref = sub { print "AnonSub\n" };

##</code><code>##

use Data::Dumper;

sub make_hash_from_arrays {
  my ($aref1, $aref2) = @_;
  
  my %hash;

  $hash{$_} = shift @$aref2 foreach (@$aref1);

  print Dumper(\%hash);
}

my @a = ('a', 'b', 'c', 'd');
my @b = (1, 2, 3, 4);

make_hash_from_arrays(\@a, \@b);

##</code><code>##

    $address{Bernd} = 'Bernd Dulfer|Kapellenstr. 1|bdulfer@sybase.com';
    $email = (split(/\|/, $address{bernd}))[2];

##</code><code>##

    $name{Bernd}  = 'Bernd Dulfer';
    $str{Bernd}   = 'Kapellenstr. 1';
    $email{Bernd} = 'bdulfer@sybase.com';

    print_address($name{Bernd}, $str{Bernd});

##</code><code>##

+----------\
| address   >           
+----------/             
      |
+#######################+
+"""""""""""""""""""""""+ 
+-----------\ +---------+  
|   Bernd    >|    O----+----->+##################################+
+-----------/ +---------+      +""""""""""""""""""""""""""""""""""+ 
                               +-----------\ +--------------------+ 
                               |   Name     >|  Bernd Dulfer      |
                               +-----------< +--------------------+
                               |   Str      >|  Kapellenstr. 1    |
                               +-----------< +--------------------+ 
                               |   EMail    >|  bdulfer@sybase.com|
                               +-----------/ +--------------------+ 


$address{Bernd} = {
                      Name    =>  'Bernd Dulfer',
                      Str     =>  'Kapellenstr. 1',
                      EMail   =>  'bdulfer@sybase.com'
                  };

$email = $address{Bernd}->{EMail};
print_address($address{Bernd});

##</code><code>##

+----------\
| address   >
+----------/
      |
+##########+
+""""""""""+
+----\ +---+
|Bernd>| O-+->+###########################+
+----/ +---+  +"""""""""""""""""""""""""""+
              +------\ +------------------+
              |Name   >|Bernd Dulfer      |
              +------< +------------------+
              |Str    >|Kapellenstr. 1    |
              +------< +------------------+
              |EMail  >|bdulfer@sybase.com|
              +------< +------------------+
              |Books  >|        O---------+->+#####################+
              +------/ +------------------+  +"""""""""""""""""""""+
                                             |Lord of the Rings    |
                                             +---------------------+
                                             |Hitchhikers Guide ...|
                                             +---------------------+
                                             |The Color of Magic   |
                                             +---------------------+



$address{Bernd} = {
                      Name    =>  'Bernd Dulfer',
                      Str     =>  'Kapellenstr. 1',
                      EMail   =>  'bdulfer@sybase.com',
                      Books   =>  [
                                   'Lord of the Rings',
                                   'Hitchhikers Guide to the Galaxy',
                                   'The Color of Magic'
                                  ]
                  };

##</code><code>##

    $s   = 'qwertz';
    $sref = \$s;
    print ${$sref}, "\n";
    print $$sref, "\n";

##</code><code>##

qwertz
qwertz

##</code><code>##

    $, = ':';
    @a    = (123, 456, 789);
    $aref = \@a;
    print @{$aref}, "\n";
    print @$aref, "\n";

##</code><code>##

123:456:789
123:456:789

##</code><code>##

    ${$aref}[1]
or
    $$aref[1]

##</code><code>##

    $address{Bernd} = {
                       Name    => 'Bernd Dulfer',
                       Str     => 'Kapellenstr. 1',
                       EMail   => 'bdulfer@sybase.com',
                       Books   => [
                                   'Lord of the Rings',
                                   'Hitchhikers Guide to the Galaxy',
                                   'The Color of Magic'
                                  ]
                      };
    print 'Name: ', $address{Bernd}->{Name}, "\n";

##</code><code>##

Name: Bernd Dulfer

##</code><code>##

    $address{Bernd}->{Books}->[3] = 'Goedel, Escher, Bach - An Eternal Golden Braid';

##</code><code>##

    push @{$address{Bernd}->{Books}}, 'Icerigger';

##</code><code>##

%authors = (
            Tolkien   => [
                          'The Silmarillion',
                          'Unfinished Tales'
                         ],
            Pratchett => [;
                          'Guards! Guards!',
                          'Feet of Clay'
                         ]
           )

##</code><code>##

$address{Bernd}->{Authors} = \%authors;

##</code><code>##

push @{$authors{Tolkien}}, 'The Hobbit';

##</code><code>##

    #!/usr/bin/perl

    use strict;
    use warnings;

    use Data::Dumper;

    my %address;
    $address{Bernd} = {
                       Name    => 'Bernd Dulfer',
                       Str     => 'Kapellenstr. 1',
                       EMail   => 'bdulfer@sybase.com',
                       Books   => [
                                   'Lord of the Rings',
                                   'Hitchhikers Guide to the Galaxy',
                                   'The Color of Magic'
                                  ]
                      };

    $address{Bernd}->{Books}->[3] = 'Goedel, Escher, Bach - An Eternal Golden Braid';
    push @{$address{Bernd}->{Books}}, 'Icerigger';

    $address{Bernd}->{Authors}->{Tolkien} = ['Silmarillion', 'Unfinished Tales'];

    print Dumper(\%address);

##</code><code>##

$VAR1 = {
          'Bernd' => {
                       'Authors' => {
                                      'Tolkien' => [
                                                     'Silmarillion',
                                                     'Unfinished Tales'
                                                   ]
                                    },
                       'Books' => [
                                    'Lord of the Rings',
                                    'Hitchhikers Guide to the Galaxy',
                                    'The Color of Magic'
                                    'G&ouml;del, Escher, Bach - An Eternal Golden Braid',
                                    'Icerigger'
                                  ],
                       'EMail' => 'bdulfer@sybase.com',
                       'Str' => 'Kapellenstr. 1',
                       'Name' => 'Bernd Dulfer'
                     }
        };

##</code><code>##

#Short   Name           Str              EMail                Books
Bernd   |Bernd Dulfer  |Kapellenstr. 1  |bdulfer@sybase.com  |(Lord of the Rings|Hitchhikers Guide ...|The Color of Magic)
Bilbo   |Bilbo Baggins |Bagend          |                    |(The Red Book)

##</code><code>##

 1:    my %addresses;
 2:
 3:    open ADDRESSES, 'addresses.dat' or die "Cannot open addresses.dat: $!\n";
 4:    while (<ADDRESSES>) {
 5:      next if /^#/;
 6:      my ($short, $name, $str, $email, $books) = split(/\s*\|/, $_, 5);
 7:      $addresses{$short} = {
 8:                             Name    => $name,
 9:                             Str     => $str,
10:                             EMail   => $email
11:                            };
12:      $books =~ tr/()//d;
13:      push @{$addresses{$short}->{Books}}, split /\|/, $books;
14:    }
15:    close ADDRESSES;

##</code><code>##

foreach (@{$address{Bernd}->{Books}}) {
  print $_, "\n";
}

##</code><code>##

foreach (keys %{$address{Bernd}->{Authors}}) {
  print $_, "\n";
  foreach (@{$address{Bernd}->{Authors}->{$_}}) {
    print "\t", $_, "\n";
  }
}

##</code><code>##

    Package Mod;

    my $callback;

    sub set_callback {
      $callback = shift;
    }

    sub do_something {
      do_this();
      do_that();

      &$callback;

      do_something_else();
    }

    .
    .
    .

    1;

    __END__


    #!/usr/bin/perl

    use strict;
    use warnings;

    use Mod;

    Mod::set_callback(\&print_rubbish);

    Mod::do_something();

    sub print_rubbish (
      print "Rubbish!\n";
    }

##</code><code>##

    %dispatch = (
                 insert => \&insert,
                 update => \&update,
                 delete => \&delete
                )

    $dispatch{$token}->($query);