How to reset an ANY so it can take on a new data type

TestClearAny.clw

  PROGRAM
  MAP
  END

    INCLUDE('debuger.inc'),ONCE
dbg          debuger

SomeGroup    GROUP
LongVar       LONG
RealVar       REAL
             END 
CurrentField ANY
  CODE
  dbg.MG_Init('TestClearAny')

  SomeGroup.LongVar = 42 
  SomeGroup.RealVar = 56.789

  CurrentField &= WHAT(SomeGroup, 1)
  dbg.ODS('1: CurrentField['& CurrentField &']') ! expecting 42 
                                                 ! got       42

  CurrentField = 'Hello There' 
  dbg.ODS('2: CurrentField['& CurrentField &']') ! expecting 0 
                                                 ! got       0

  CLEAR(CurrentField)                            ! FAILS to reset the ANY so it can take on a new data type
  CurrentField = 'Round #2'
  dbg.ODS('3: CurrentField['& CurrentField &']') ! hoping for 'Round #2' 
                                                 ! got        0

  CurrentField &= NULL                           ! SUCCEEDS resetting the ANY so it can take on a new data type
  CurrentField = 'Yet another try'
  dbg.ODS('4: CurrentField['& CurrentField &']') ! hoping for 'Yet another try'
                                                 ! got        'Yet another try