PadWalker has some serious problems when it comes to file-level lexical variables. Consider the following Perl script and Perl module: 
use strict;
use Devel::Size qw(total_size);
use Data::Dumper;
use TestModule;

my $h = TestModule::get_mem();
foreach my $name (keys(%$h)) {
    my $ref = $h->{$name};
    my $mem = total_size($ref);
    print("$name - $mem bytes\n");
    print(Dumper($ref));
    print("\n");
    }

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package TestModule;

use strict;
use PadWalker qw(peek_my);

my $str = 'abcxyzabcxyzabcxyzabcxyz';
my $h = { x => 'abcabcabcabcabc', y => 'xyzxyzxyzxyzxyz'};
my $l = ['abcdefghi', 'stuvwxyz'];

sub get_mem {

my $str1 = 'abcxyzabcxyzabcxyzabcxyz';
my $h1 = { x => 'abcabcabcabcabc', y => 'xyzxyzxyzxyzxyz'};
my $l1 = ['abcdefghi', 'stuvwxyz'];

return peek_my(0);
}

1;

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It produces the following output (I'm doing this on Windows using ActivePerl, PadWalker version 2.2). I'm particularly intrigued by the fact that it reports the variable $str of having size 88 bytes (which is correct), while Data::Dumper says that it's a reference to undef! 
$str1 - 52 bytes
$VAR1 = \'abcxyzabcxyzabcxyzabcxyz';

$h - 16 bytes
$VAR1 = \undef;

$h1 - 230 bytes
$VAR1 = \{
            'y' => 'xyzxyzxyzxyzxyz',
            'x' => 'abcabcabcabcabc'
          };

$l1 - 132 bytes
$VAR1 = \[
            'abcdefghi',
            'stuvwxyz'
          ];

$str - 52 bytes
$VAR1 = \undef;

$l - 16 bytes
$VAR1 = \undef;

[download]

In reply to Re^4: Finding file level lexical variables by johndeighan
in thread Finding file level lexical variables by johndeighan

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