Submitted for your perusal: 

#!/usr/bin/perl

use Data::Dumper;
my $var = "Yak";
${ 'Yakkity::' . $var . '::a' } = 42;
print "a = $Yakkity::Yak::a\n";
print Dumper \%Yakkity::Yak::;
print "Undeffing symbol table\n";
undef %Yakkity::Yak::;
print "a = $Yakkity::Yak::a\n";
print Dumper \%Yakkity::Yak::;
print "Undeffing glob\n";
undef *Yakkity::Yak::a;
print "a = $Yakkity::Yak::a\n";
print Dumper \%Yakkity::Yak::;

[download]

And the output: 

a = 42
$VAR1 = {
          'a' => *Yakkity::Yak::a
        };
Undeffing symbol table
a = 42
$VAR1 = {};
Undeffing glob
a = 
$VAR1 = {};

[download]

So, what's going on here? How does perl know how to find $Yakkity::Yak::a after the package's symbol table is gone? Shouldn't *Yakkity::Yak::a have been deleted with it? Or does another reference to it exist outside the symbol table? If so, where? Suppose I were creating dynamic packages at runtime and I want to make sure all the stuff in them gets destroyed. How would I ensure that?

In reply to Undefining symbol tables and globs and things, oh my by friedo

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