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package Library::OReilly;
use Class::Std;
{
my %book; # Not an attribute hash; shared storage for class
sub add_book {
my ($class, $title, $book_data) = @_;
$book{$title} = $book_data;
}
# Book titles accumulate throughout the libraries...
sub titles :CUMULATIVE {
return keys %book;
}
# Treat every undefined method call as a request for books
# with titles containing the method name...
sub AUTOMETHOD {
# Name of the desired method is passed in $_...
my $book_title = $_;
# If that name matches any of the book titles, return those titles...
if (my @matches = grep { /$book_title/ } keys %book) {
return sub{ @book{@matches} };
}
# Otherwise fail...
return;
}
}
package Library::All;
use base qw( Library::OReilly );
{
my %book;
sub add_book {
my ($class, $title, $arg_ref) = @_;
$book{$title} = $arg_ref;
}
sub titles :CUMULATIVE {
return keys %book;
}
sub AUTOMETHOD {
my $book_title = $_;
if (my @matches = grep { /$book_title/ } keys %book) {
return sub{ @book{@matches} };
}
return;
}
}
package main;
Library::OReilly->add_book(
'Programming Perl' => { ISBN=>596000278, year=>2000 }
);
Library::All->add_book(
'Object Oriented Perl' => { ISBN=>1884777791, year=>2000 }
);
print join "\n", Library::All->titles();
print "\n-------\n";
use Data::Dumper 'Dumper';
print Dumper(Library::All->Programming());
print "\n-------\n";
print Dumper(Library::All->Python());
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