anchor.diff:  
   (* PKCS7 Padding *)
   
  -let padPKCS7 (length: int) (bytes: byte seq) : byte seq =
  +let padPKCS7 (length: int) (bytes: byte seq) : byte [] =
       let targetLen = length - (Seq.length bytes % length)
       let padLen = if targetLen > 0 then targetLen else Seq.length bytes
       let pad = repeat (byte padLen)
  -    Seq.append bytes (Seq.take padLen pad)
  +    Seq.append bytes (Seq.take padLen pad) |> Seq.toArray
           
   (* AES *)
   
  
positive.code:     readStream.ReadToEnd()
  *)
  
  let prepareTextECB text =
      text
      |> strToBytes
      |> padPKCS7 16
      |> Seq.toArray
      |> Array.chunkBySize 16
  
  let AESEncryptECB (key: string) (input: byte [] []) : byte [] =
  
negative.code:         | x::y::[] -> let encrypted = encrypt x y
                        List.rev (encrypted::acc)
          | x::y::xs -> let encrypted = encrypt x y
                        applyCBCEncrypt (encrypted::xs) key (encrypted::acc)
  
  let rec applyCBCDecrypt blocks key acc : byte [] list =
      let decrypt x y = AESDecryptECB key y |> Array.ofSeq |> xor x |> Seq.toArray
  