#!/usr/bin/perl
use strict;
use warnings;

BEGIN { print "can=", __PACKAGE__->can('fred'), ";\n"; }
sub fred { print "fred\n"; }
print "can=", __PACKAGE__->can('fred'), ";\n";
fred;
undef &fred;
print "can=", __PACKAGE__->can('fred'), ";\n";
fred;

##</code><code>##

Use of uninitialized value in print at test.pl line 5.
can=;
can=CODE(0x81199b4);
fred
can=CODE(0x81199b4);
Undefined subroutine &main::fred called at test.pl line 11.