:~$ perl -MDevel::Peek -E'"42"=~/(\d+)/; say $1; Dump $1; $a=$1+1; Dump $1; say $1; Dump $1' 2>&1 |grep IV
  IV = 0
  IV = 42
  IV = 42
:~$ 

##</code><code>##

~$ perl -MDevel::Peek -E'"42"=~/(\d+)/; say $1; Dump $1; $a=$1+1; Dump $1; say $1; Dump $1' 2>&1 |grep FLAGS
  FLAGS = (GMG,SMG,POK,pPOK)
  FLAGS = (GMG,SMG,IOK,POK,pIOK,pPOK)
  FLAGS = (GMG,SMG,POK,pPOK)