     */
     func createBlock(stringData: StringData, withNextID nextStringID:UID) -> UID {
         
-        var pos = registerBlock()
-        
-        var header = StringStoreHeader()
+        let pos = registerBlock()
+        
+        let header = StringStoreHeader()
         header.stringHash = stringData.hash
         header.nextStringID = nextStringID
         header.encodingUTF8 = stringData.encoding == NSUTF8StringEncoding

    
    override func deleteBlock(uid: UID) -> CUnsignedLongLong {
        
        var pos = self.seekToFileID(uid)
        
        var header : StringStoreHeader = readHeader()
        
        if header.nextStringID > 0 {
            deleteBlock(header.nextStringID)

        header.used = true
        header.bufferLength = UInt8(stringData.length)
        
        let data : NSData = stringData.stringData.extendSize(BUFFER_LEN)
        
        writeHeader(header)
        write(data);
