$a = '           fred and bill        ';;
Dump $a;;
SV = PV(0x15be50) at 0x1b7ad8
  REFCNT = 1
  FLAGS = (POK,pPOK)
  PV = 0x1d3558 "           fred and bill        "\0
  CUR = 32
  LEN = 40

$a =~ s[^\s*|\s*$][]g;;
Dump $a;;
SV = PV(0x15be50) at 0x1b7ad8
  REFCNT = 1
  FLAGS = (POK,pPOK)
  PV = 0x1d3558 "fred and bill"\0
  CUR = 13
  LEN = 40