I am looking for a way to unload (and after that, reload) a module at run time. I have found this code: https://metacpan.org/source/ALEXMV/Module-Refresh-0.17/lib/Module/Refresh.pm and am using bits of it: 
# class.pm

package class;

use 5.014;
use strict;
use warnings;
use autodie;

sub new {bless {}, 'class'}

sub talk {print "111513\n"}

# code.pl

#!/usr/bin/env perl

use strict;
use warnings;
use autodie;

use 5.014;
use Data::Dumper;

BEGIN {
    $^P |= 0x10;
 
    eval 'sub DB::sub' if $] < 5.008007;
}

sub _unload_subs {
    my $file = shift || return;
 
    for my $sym ( grep { index( $_, "$file:" ) == 0 } keys %DB::sub ) 
+{
        eval { undef &$sym };
        warn "$sym: $@\n" if $@;
        delete $DB::sub{$sym};
    }
 
    return 1;
}


do './class.pm';
my $obj = class->new();
$obj->talk;
delete $INC{'./class.pm'};
_unload_subs('class');
#say Dumper \%DB::sub;
my $dummy = <>; # we change class.pm meanwhile
do './class.pm';
say $@ if $@;
$obj = class->new();
$obj->talk;

# results:

# $ ./code.pl 
# 111513
#
# panic: attempt to copy freed scalar 12dcbf0 to 1414870 at ./class.pm
+ line 3, <> line 1.
#
# Undefined subroutine &class::new called at ./code.pl line 38, <> lin
+e 1.

# Removing "use 5.014" from class.pm fixes the panic but is there a be
+tter fix?
# Also, why is this panic error happening?

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In reply to Reloading a module at run time by alpha

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