$ perl -MDevel::Peek -e'$x="abc"; %h=(x=>"abc"); sub f { Dump($_[0]) } f($x); f($h{x});'
SV = PV(0x816a040) at 0x817bc40
  REFCNT = 1
  FLAGS = (POK,pPOK)
  PV = 0x8177bf0 "abc"\0
  CUR = 3
  LEN = 4
SV = PV(0x816a098) at 0x816c158
  REFCNT = 1
  FLAGS = (POK,pPOK)
  PV = 0x817d920 "abc"\0
  CUR = 3
  LEN = 4