def step_pointer(caller, step=1):
 ptr = caller.ndb.batch_stackptr
 stack = caller.ndb.batch_stack
 nstack = len(stack)
 if ((ptr + step) <= 0):
  caller.msg('{RBeginning of batch file.')
 if ((ptr + step) >= nstack):
  caller.msg('{REnd of batch file.')
 caller.ndb.batch_stackptr = max(0, min((nstack - 1), (ptr + step)))

def step_pointer ( caller , step = 1 ) : ptr = caller . ndb . batch_stackptr stack = caller . ndb . batch_stack nstack = len ( stack ) if ( ( ptr + step ) <= 0 ) : caller . msg ( '{RBeginning of batch file.' ) if ( ( ptr + step ) >= nstack ) : caller . msg ( '{REnd of batch file.' ) caller . ndb . batch_stackptr = max ( 0 , min ( ( nstack - 1 ) , ( ptr + step ) ) )
step in stack .