Can you maybe do with just using overload? Then you can control what happens when your object is used as a string, used as a number and other things... Your example would fit this usage:

package My::DateObject;
use DateTime;
use vars '$AUTOLOAD';
use Carp qw(croak);

use overload q{""} => 'as_string';

sub new {
    my ($class, %args) = @_;
    my $self = {
      dt => DateTime->now(),
      %args,
    };
    bless $self => $class;
};

sub as_string {
    $_[0]->{ dt }->ymd("-");
};

sub DESTROY {}; # we have AUTOLOAD

sub AUTOLOAD {
    # blindly delegate to $self->{dt}
    $AUTOLOAD =~ /::(\w+)$/
        or croak "Malformed method '$AUTOLOAD'";
    my $method = $1;
    $_[0]->{dt}->$method(@_);
};

package main;

my $do = My::DateObject->new();

print "As string: $do\n";
print "As object: ", $do->mdy("/"),"\n";

[download]

Update: Fixed lots of typos in the untested code

In reply to Re: dualvar for a reference-string combination by Corion
in thread dualvar for a reference-string combination by Anonymous Monk

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