PDL doesn't behave as a normal Perl object oriented module. Its quirks are described in PDL::Objects which also shows how to subclass it, which is exactly what you need. 
package PDL::CV;
use parent qw{ PDL };  # Tell Perl what your parent class is.
sub rp {
    my ($self, $input) = @_;
    $self .= $input->reshape($self->dims);
    return $self
}

sub new {
    my $class = shift;
    return bless {
        PDL => shift,  # See PDL::Objects for details.
    }, $class
}

[download]

You also need to instantiate the new class: 

my $d = PDL::CV->new(sequence(4,5));
my $t = pdl sequence(100,5,5);
$d(0,1:4)->rp($t(0,0,1:4));

[download]

map{substr$_->[0],$_->[1]||0,1}[\*||{},3],[[]],[ref qr-1,-,-1],[{}],[sub{}^*ARGV,3]

In reply to Re: how to export a method by choroba
in thread how to export a method by toothedsword

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