__PACKAGE__ does what you expect here, but I doubt that you can subclass from the code.
Using of __PACKAGE__ makes subclass from this class most of the time impossible. Propably this is not what you do.
yy is the subclass and the expected output should be YYYY but you get XXYY since the package is hardcoded. 
package xx;
sub new { bless {}, shift }
sub instance { __PACKAGE__->new }
sub print    { print "XX" }

package yy;
@ISA = qw/xx/;
sub print { print "YY" }

package main;
my $yy = yy->instance;
$yy->print;
my $yyy = yy->new;
$yyy->print

[download]
Boris

In reply to Re: __PACKAGE__ in anonysub by borisz
in thread __PACKAGE__ in anonysub by thpfft

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.