Hi,

I'm about to embark on an oo development project in perl and require (no pun intended) a way of implementing an interface in a fool proof fashion with compile time enforcement on required virtual methods. After having read through some info on abstract classes and interfaces, I decided to go with Class::Virtually::Abstract because it seemed to best meet my needs. Incidentally, I'm not sure why but I suspect overriding bless and import is fundamentally evil.

Anyway, the following code compiles, but there are still a few missing pieces of the puzzle. Namely:

• How would I implement virtual attribtues?
• How can I get the class->virtual_methods for both interfaces? (iface2 seems to almost overwrite iface1)
• Is this the best way to create and implement the interfaces?
• What about a template constructor, is that possible and where would it reside?

Any good practices or advice welcome,

Thanks.

####################################
package iface2;
print "\n\n",__PACKAGE__,"\n\n";
use base qw(Class::Virtually::Abstract);
__PACKAGE__->virtual_methods(qw(new iface2_method));
1;
__END__


####################################
package iface1;
print "\n\n",__PACKAGE__,"\n\n";
use base qw(Class::Virtually::Abstract);
__PACKAGE__->virtual_methods(qw(new iface1_method));
1;
__END__


####################################
package class;
use base qw(iface1 iface2);

# See what methods we're obligated to implement.
my @must_implement = __PACKAGE__->virtual_methods;
print "\n",__PACKAGE__," must implement @must_implement\n\n";

# Check to make sure this PACKAGE implemented everything
my @missing = __PACKAGE__->missing_methods;
die __PACKAGE__ . ' forgot to implement ' . join ', ', @missing if @mi
+ssing;

sub new {
    my ( $class ) = shift;
    my $self = {};
    bless $self, $class;
    return $self;
}

sub iface1_method {
    my ( $self, $arg ) = @_;
    print"\nclass->iface1_method : called with $arg\n\n";
    return $self;
}

sub iface2_method {
    my ( $self, $arg ) = @_;
    print"\nclass->iface2_method : called with $arg\n\n";
    return $self;
}

####################################
# bootstrap
####################################
#!/ms/dist/perl5/bin/perl5.8

use Data::Dumper;
use class;
 
my $c = new class;

$c->iface1_method("passed in to 1");
$c->iface2_method("passed in to 2");

print "Dump of object: class:\n",Dumper $c;
print "\nEND \n\n";
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