or download this
Watchpoint 0: @{[ $z++, map { (caller $_)[0..3],"\n" } 1..3 ]} chan
+ged:
old value: '0', 'DB', '/home/lanx/.perldb', '3', 'DB::eval', '
', 'DB', '/usr/share/perl/5.10/perl5db.pl', '1953', 'DB::new_eval', '
', 'Config', '/usr/lib/perl/5.10/Config.pm', '62', 'DB::DB', '
'