El Módulo Devel::Peek

Estudie la siguiente ejecución con el depurador. El módulo Devel::Peek nos permite observar la estructura interna de las variables en el intérprete:

lhp@nereida:~/Lperl/src$ perl -MDevel::Peek -wd weakenwithcopy.pl
main::(weakenwithcopy.pl:3):    my ($ref, $copy);
main::(weakenwithcopy.pl:4):    {
  DB<1> c 10
main::(weakenwithcopy.pl:10):   print $$ref;
  DB<2> -
1:      use strict;
2:      use Scalar::Util qw(weaken);
3:      my ($ref, $copy);
4       {
5:        my $var = "hola\n";
6:        $ref = \$var;
7:        weaken($ref);
8:        $copy = $ref;
9       }
10==>   print $$ref;
  DB<2> Dump $ref
SV = RV(0x817b328) at 0x823a050
  REFCNT = 2
  FLAGS = (PADBUSY,PADMY,ROK,WEAKREF)
  RV = 0x814f7e0
  SV = PVMG(0x83dcb80) at 0x814f7e0
    REFCNT = 1
    FLAGS = (PADBUSY,PADMY,RMG,POK,pPOK)
    IV = 0
    NV = 0
    PV = 0x8238fa8 "hola\n"\0
    CUR = 5
    LEN = 8
    MAGIC = 0x83e3368
      .............................
  DB<3> Dump $copy
SV = RV(0x817b324) at 0x814f810
  REFCNT = 2
  FLAGS = (PADBUSY,PADMY,ROK)
  RV = 0x814f7e0
  SV = PVMG(0x83dcb80) at 0x814f7e0
    REFCNT = 1
    FLAGS = (PADBUSY,PADMY,RMG,POK,pPOK)
    IV = 0
    NV = 0
    PV = 0x8238fa8 "hola\n"\0
    CUR = 5
    LEN = 8
    MAGIC = 0x83e3368
      .............................