$ perl -MDevel::Peek -e'$x="1e1"; 0+$x; Dump($x)'
SV = PVNV(0xc27550) at 0xc48bc8
  REFCNT = 1
  FLAGS = (IOK,NOK,POK,pIOK,pNOK,pPOK)
  IV = 10
  NV = 10
  PV = 0xc37d80 "1e1"\0
  CUR = 3
  LEN = 16
$perl -MDevel::Peek -e'$x="1.1e1"; 0+$x; Dump($x)'
SV = PVNV(0x1513550) at 0x1534bc8
  REFCNT = 1
  FLAGS = (IOK,NOK,POK,pIOK,pNOK,pPOK)
  IV = 11
  NV = 11
  PV = 0x1523d80 "1.1e1"\0
  CUR = 5
  LEN = 16