sub numbers {
  my ($class,$number) = @_;
  if ( /(\d+)/ ) {
    return ( $1, { msg => 'ok' } );
  } else {
    return ( undef, { msg => 'numbers, please' } );
  }
}
...
my ($age,$stuff) = Validate->numbers( ... );
unless ( $age ) {
  push @errors, $stuff->{msg};
}