tie @array, 'Tie::ArrayXYZ';
tied(@array)->method(@args);

##</code><code>##

$obj = tie @array, 'Tie::ArrayXYZ';
$obj->method(@args);

##</code><code>##

method(@array, @args);

##</code><code>##

package Tie::ArrayXYZ;

use Tie::Functions qw( @ changeXYZ );

# ...

sub CHANGEXYZ {
  my ($obj, $new_xyz) = @_;
  $obj->{XYZ} = $new_xyz;
}

1;

##</code><code>##

use Tie::ArrayXYZ;

tie @array, 'Tie::ArrayXYZ', $some_xyz;
# ...
tied(@array)->CHANGEXYZ($new_xyz);

##</code><code>##

use Tie::ArrayXYZ;

tie @array, 'Tie::ArrayXYZ', $some_xyz;
# ...
changeXYZ(@array,$new_xyz);

##</code><code>##

sub main::changeXYZ (\@@) {
  my $arg = shift;
  my $obj = tied @$arg;
  Carp::croak(
    "First arg to main::changeXYZ must be array tied to Tie::ArrayXYZ"
  ) unless defined($obj) and $obj->isa("Tie::ArrayXYZ");
  return $obj->CHANGEXYZ(@_);
}

##</code><code>##

use Tie::Functions VARTYPE, FUNCTIONS;

##</code><code>##

package Tie::Functions;

use Carp;

my %trans = qw( $ scalar @ array % hash * glob );

sub import {
  shift;
  my $type = shift;
  my $pkg = caller(0);
  my $ppkg = caller(1);

  croak "Type must be '\$', '\@', '%', '*', not '$type'."
    unless $type eq '$' or $type eq '@' or $type eq '%' or $type eq '*';

  eval qq[     
    sub ${ppkg}::$_ (\\$type\@) {
      my \$arg = shift;
      my \$obj = tied $type\$arg;
      Carp::croak(
        "First arg to ${ppkg}::$_ must be $trans{$type} tied to $pkg"
      ) unless defined(\$obj) and \$obj->isa("$pkg");
      return \$obj->\U$_\E(\@_);
    }
  ] for @_;
}

1;