rekey
  
  Description:
  public void rekey (void* object, void* new_key)
  
  
    Changes the key for object to new_key, atomically.
    It is considered a programming error if object is not found in this. In such case the function 
      will emit a terminal warning and return.
    Parameters:
    
      
        | this | a ObjectBag | 
      
        | object | a Object | 
      
        | new_key | a new key for object |