OK, chromatic's suggestion worked fine:

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

# Undefine a subroutine safely, by name.
# From a method described by chromatic.
sub undefSub
{
 no strict 'refs';
 my $name = shift;

 # save the glob...
 local *old = *{$name};

 # and restore everything else
 local *new;
 foreach my $type (qw(HASH IO FORMAT SCALAR ARRAY))
 {
  my $elem = *old{$type};
  next if !defined($elem);
  *new = $elem;
 }
 *{$name} = *new;
}

package A;
sub A { print "A::A $_[0]\n" }

package B;
@B::ISA = 'A';
$B::A   = "i'm \$B::A\n\n";

package main;

A->A;
B->A;    # calls A::A
print $B::A;

*{B::A} = sub { print "B::A $_[0]\n" };

A->A;
B->A;    # now calls B::A
eval 'print $B::A';

undefSub('B::A');

A->A;
B->A;  # now calls A::A
eval 'print $B::A';  # still intact!

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In reply to Re: Undefining subroutines and inheritance by bikeNomad
in thread Undefining subroutines and inheritance by bikeNomad

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