Very interesting. I created the following package:

package Scrap::Foo;
use strict;

sub bar {
    my $dummy;
    $dummy->{_init}->{__PACKAGE__}++;
    return $dummy;
}
1
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And my test code:

use strict;
use Scrap::Foo;
use Data::Dumper;
my $dummy = Scrap::Foo::bar();
print Dumper $dummy;
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Generated this output:

$VAR1 = {
          '_init' => {
                       '__PACKAGE__' => '1'
                     }
        };
[download]

And the fix:

my $package = __PACKAGE__;
$dummy->{_init}->{$package}++;
[download]

Thanks for the info. Now who wants to tell Damian? :)

Cheers,
Ovid

Update: japhy's unary fix is not only shorter, but it should be faster as it doesn't involve creating a variable for no other reason than throwing it away.

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The "unary +" fix is shorter...

$foo->{+__PACKAGE__} = 1;
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Hmm, patching a book isn't quite so easy!

_____________________________________________________
Jeff japhy Pinyan: Perl, regex, and perl hacker.
s++=END;++y(;-P)}y js++=;shajsj<++y(p-q)}?print:??;

I was toying around with __PACKAGE__ just yesterday. For interpolation into strings, you can do the scalar ref-deref trick:

my $str = "I'm in package ${\__PACKAGE__}"
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   MeowChow                                   
               s aamecha.s a..a\u$&owag.print