#!/usr/bin/perl

package AccessMutate;

# Silly package which returns old values
# when attributes are mutated
sub new {
  bless {};
}

sub foo {
  my $self = shift;
  return $self->{foo} unless @_;
  my $old = $self->{foo};
  $self->{foo} = shift;
  $old;
}

sub bar {
  my $self = shift;
  return $self->{bar} unless @_;
  my $old = $self->{bar};
  $self->{bar} = shift;
  $old;
}

package C::P::MC;

sub new {
  my $class = shift;
  my $obj = shift;
  bless \shift, $class;
}

# Call the object's method. If called
# in scalar context, returns the proxy
# object. If called in list context, returns
# object, and return value.
# (Update - drawback: assumes
# that the method returns a scalar.., could
# probably be fixed with some wantarray logic)
sub AUTOLOAD {
  my $self = shift;
  my $obj = $$self;
  (my $method = $AUTOLOAD) =~ s/.*:://;
  my $ret = $obj->$method(@_);
  return $obj, $ret, $self;
}

sub DESTROY { 1 }

package main;

use strict;
use warnings;

# Return AM object
my ($obj1) = C::P::MC
  ->new(AccessMutate->new)
  ->foo(3)
  ->bar(2);

print $obj1->foo,"\n";
print $obj1->bar,"\n";

# Return CPMC object
my $obj2 = C::P::MC
  ->new(AccessMutate->new)
  ->foo(3)
  ->bar(2);

my (undef, $foo) = $obj2->foo;
my (undef, $bar) = $obj2->bar;

print "$foo $bar\n";
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