use strict;
use Devel::Peek;

my $a;
Dump($a);
$a=4;
Dump($a);
$a eq "13";
Dump($a);
$a++;
Dump($a);
print $a;
Dump($a);

##</code><code>##

C:\Users\ian>perl test.pl
SV = NULL(0x0) at 0x1d9ec1c
  REFCNT = 1
  FLAGS = (PADMY)
SV = IV(0x1d9ec18) at 0x1d9ec1c
  REFCNT = 1
  FLAGS = (PADMY,IOK,pIOK)
  IV = 4
SV = PVIV(0x1d91c34) at 0x1d9ec1c
  REFCNT = 1
  FLAGS = (PADMY,IOK,POK,pIOK,pPOK)
  IV = 4
  PV = 0x1dbdf84 "4"\0
  CUR = 1
  LEN = 4
SV = PVIV(0x1d91c34) at 0x1d9ec1c
  REFCNT = 1
  FLAGS = (PADMY,IOK,pIOK)
  IV = 5
  PV = 0x1dbdf84 "4"\0
  CUR = 1
  LEN = 4
SV = PVIV(0x1d91c34) at 0x1d9ec1c
  REFCNT = 1
  FLAGS = (PADMY,IOK,POK,pIOK,pPOK)
  IV = 5
  PV = 0x1dbdf84 "5"\0
  CUR = 1
  LEN = 4
5

##</code><code>##

SV = NULL(0x0) at 0x1d9ec1c
  REFCNT = 1
  FLAGS = (PADMY)

##</code><code>##

SV = IV(0x1d9ec18) at 0x1d9ec1c
  REFCNT = 1
  FLAGS = (PADMY,IOK,pIOK)
  IV = 4

##</code><code>##

SV = PVIV(0x1d91c34) at 0x1d9ec1c
  REFCNT = 1
  FLAGS = (PADMY,IOK,POK,pIOK,pPOK)
  IV = 4
  PV = 0x1dbdf84 "4"\0
  CUR = 1
  LEN = 4

##</code><code>##

SV = PVIV(0x1d91c34) at 0x1d9ec1c
  REFCNT = 1
  FLAGS = (PADMY,IOK,pIOK)
  IV = 5
  PV = 0x1dbdf84 "4"\0
  CUR = 1
  LEN = 4

##</code><code>##

SV = PVIV(0x1d91c34) at 0x1d9ec1c
  REFCNT = 1
  FLAGS = (PADMY,IOK,POK,pIOK,pPOK)
  IV = 5
  PV = 0x1dbdf84 "5"\0
  CUR = 1
  LEN = 4