     
     public func addObject(aObj: O) -> UID {
         
-        var pos = registerBlock()
-        var uid = calculateID(pos)
+        let pos = registerBlock()
+        let uid = calculateID(pos)
         
         self.writeBlock(aObj, atPos: pos)
         

    
    func deleteBlock(aID: UID) -> CUnsignedLongLong {
        
        var pos = self.seekToFileID(aID)
        
        var block = Block(used: false)
        
        writeBlock(block)
        

    
    public func createObject() -> O {
        
        let result = O()
        
        addObject(result)
        
