undef *$field;

Gotta be careful with that because it will blow away more than just the $field method. Say bye-bye to the $field array the $field hash and everything else in the $field stash...

my $obj = Bar->new()

$Bar::faz = 100;
print '$Bar::faz = ' . $Bar::faz . "\n";

$obj->destroy_methods();

print '$Bar::faz = ' . $Bar::faz . "\n";
__END__
$Bar::faz = 100
$Bar::faz =

Doh!
[download]

As written, it might also mess up the method lookup cache that perl uses to determine which methods are overridden and which aren't.

What you'd really like is a way to localize the subroutine portion of the stash, but Perl doesn't provide a clean way to do that.

Before you go much further down this path, you really should read the highly enlightening discussion at: Undefining subroutines and inheritance

-Blake