b $var        Set breakpoint at first line of 
              subroutine referenced by $var.

##</code><code>##

$ cat namevsref.pl
use warnings;
use strict;

my $time = 1;

my $x = sub {
  print "Inside sub. time = ".($time++)."\n";
};

no strict 'refs';
*{"tutu"} = $x;

$x->();
tutu();

##</code><code>##

pp2@nereida:~/src/perl/testing$ perl -wd namevsref.pl

Loading DB routines from perl5db.pl version 1.28
Editor support available.

Enter h or `h h' for help, or `man perldebug' for more help.

main::(namevsref.pl:4): my $time = 1;
  DB<1> l 1,14
1:      use warnings;
2:      use strict;
3
4==>    my $time = 1;
5
6       my $x = sub {
7:        print "Inside sub. time = ".($time++)."\n";
8:      };
9
10:     no strict 'refs';
11:     *{"tutu"} = $x;
12
13:     $x->();
14:     tutu();
  DB<2> c 11
main::(namevsref.pl:11):        *{"tutu"} = $x;
  DB<3> x $x
0  CODE(0x825a074)
   -> &main::__ANON__[namevsref.pl:8] in namevsref.pl:6-8
  DB<4> b $x
  DB<5> L
namevsref.pl:
 11:    *{"tutu"} = $x;
   break if ($x)
  DB<5> c
Inside sub. time = 1
Inside sub. time = 2
Debugged program terminated.  Use q to quit or R to restart,
  use o inhibit_exit to avoid stopping after program termination,
  h q, h R or h o to get additional info.
  DB<5>