#!/usr/bin/perl -w
use strict;

package MyCwd;
use Cwd;

sub cd
{
 warn "must assign to something!\n" if !defined(wantarray);
 my $class = shift;
 my $new_dir = shift;
 my $self = cwd;
 chdir $new_dir;
 bless(\$self, $class);
}

sub DESTROY
{
 my $self = shift;
 chdir $$self;
}

"that's it!";

##</code><code>##

package main;
use MyCwd;
use Cwd;

print cwd, "\n";

if (1)
{
 my $cwd = MyCwd->cd('..');
 {
  my $cwd = MyCwd->cd('..');
  print cwd, "\n";
 ]
 print cwd, "\n";
}

print cwd, "\n";