Here is what I tried. I think its similar to what you've tried above. Its odd but convienient that after untie'ing you are left with a variable that has the same value as was last returned from FETCH. (At least on my perl v5.6.1). So you don't need to pass a reference to the variable in order to set it after the untie (here it is accessed through a closure).
use strict;
use warnings;

package MyTied;
sub TIESCALAR {
  my ($class,$code) = @_;
  bless $code, $class;
}

sub FETCH {
  my $self = shift;
print "Untie\n";
  $self->();
}

package main;
my $var;
tie $var, 'MyTied', sub { untie $var; 4 };
print "One\n";
print "$var\n";
print "Two\n";
print "$var\n";
print "Three\n";
print "$var\n";

OUTPUT:
One
Untie
4
Two
4
Three
4

[download]
Updated. several times.

In reply to Re: How to untie oneself? by runrig
in thread How to untie oneself? by Jenda

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