At the risk of sounding like The Boy Who Cried Wolf, I really do wonder if I have discovered a bug in Array::Compare.

When running the following code:

#!/usr/bin/perl -w

use strict;
use warnings;
use Array::Compare;

my $comp1 = Array::Compare->new;
$comp1->Sep        ('|');
$comp1->Skip       ({3 => 1, 4 => 1});
$comp1->WhiteSpace (0);
$comp1->Case       (1);

my $comp2 = Array::Compare->new (
    Sep        => '|',
    WhiteSpace => 0,
    Case       => 1,
    Skip       => {3 => 1, 4 => 1}
);

my @arr1 = 0 .. 10;
my @arr2 = 0 .. 10;

if ($comp1->simple_compare (\@arr1, \@arr2)) {
    print "Arrays are the same\n";
} else {
    print "Arrays are different\n";
}

if ($comp2->simple_compare (\@arr1, \@arr2)) {
    print "Arrays are the same\n";
} else {
    print "Arrays are different\n";
}
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Under both 5.8 and 5.10 (thanks, CountZero!), I get the following warnings:

Use of uninitialized value $caller in string eq at /usr/lib/perl5/site
+_perl/5.8/Array/Compare.pm line 328.
Arrays are the same
Use of uninitialized value $caller in string eq at /usr/lib/perl5/site
+_perl/5.8/Array/Compare.pm line 328.
Arrays are the same
[download]

When I run my program under the debugger, I note that the line preceeding (327) reads:

my ($pkg, $caller) = (caller(1))[0, 3];
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and that after 327 is executed, $caller is undef.

Now, when you x (caller(1))[0, 3] within the debugger, obviously you get something a wee bit different than the program is seeing:

('DB', 'DB::eval')

However, x (caller(3))[0, 3] seems to return what I believe Array::Compare is expecting:

('main','Array::Compare::simple_compare')

It looks to me like something very weird is going on. Why isn't $caller set to Array::Compare::simple_compare? Why is $caller undef, therefore causing the "uninitialized value in string eq" as shown above?

Any insights will be greatly appreciated. Thanks in advance!