use strict;
use vars qw($obj);
use Carp qw(carp croak cluck confess);
use Cwd;

sub TIESCALAR { my $var; carp "tie:\t",\$var," = $_[0]\n"; bless \$var => shift;  }
sub FETCH     { carp "fetch:\t$_[0] == ${$_[0]}\n"; ${$_[0]}  }
sub STORE     { carp "store:\t$_[0] =  $_[1]\n"; ${$_[0]} = $_[1]}

tie $obj => 'main';
$obj = 'foo';
{
  my $x = 1;
  my $y = $obj;
  local $obj = 'bar';
}

### OUTPUT ###

tie:    SCALAR(0x8106d78) = main
        main::TIESCALAR('main') called at - line 10
store:  main=SCALAR(0x8106d78) =  foo
        main::STORE('main=SCALAR(0x8106d78)', 'foo') called at - line 11
fetch:  main=SCALAR(0x8106d78) == foo
        main::FETCH('main=SCALAR(0x8106d78)') called at - line 14
fetch:  main=SCALAR(0x8106d78) == foo
        main::FETCH('main=SCALAR(0x8106d78)') called at - line 15
store:  main=SCALAR(0x8106d78) =  
        main::STORE('main=SCALAR(0x8106d78)', undef) called at - line 15
store:  main=SCALAR(0x8106d78) =  bar
        main::STORE('main=SCALAR(0x8106d78)', 'bar') called at - line 15
store:  main=SCALAR(0x8106d78) =  foo
        main::STORE('main=SCALAR(0x8106d78)', 'foo') called at - line 13