package My::Guard;
use strict;
sub new {
    bless $_[1] => $_[0];
};
sub DESTROY {
    $_[0]->()
};

##</code><code>##

#!perl -w
package My::Guard;
use strict;
sub new {
    bless $_[1] => $_[0];
};
sub DESTROY {
    $_[0]->()
};

package main;
use strict;

sub alias {\@_};
sub localize {
    my @values = @{ +pop }; # or any other convenient method
    my $aliases=alias(@_);
    my @saved= @_;

    #warn Dumper \@saved;
    $_[$_] = $values[$_] for 0..$#values;
    My::Guard->new(sub{
        $aliases->[$_]=$saved[$_] for 0..$#saved;
    })
};

my ($a,$b)=('a','b');

print "Start\n";
print qq($a $b),"\n";

my $restore=localize($a,$b,['foo','bar']);

print "Localized\n";
print qq($a $b),"\n";
undef $restore;
print "Restored\n";
print qq($a $b), "\n";