anchor.diff:  let target = "/home/robert/.bitcoin/blocks/blk00000.dat"
   
   let stream = getByteStream target 
  -readMessages 1 stream
  +readMessages 3 stream
   
  
positive.code: module BitcoinFs.Parser
  open System
  open System.Collections.Generic
  open System.IO
  
  let getByteStream file =
  
negative.code:     let challengeScriptLength, bytesUsed = decodeVariableLengthInt bytesToProcess.[offSet + 8 .. offSet + 16]
      let offSet = offSet + 8 + bytesUsed
      let bytesUsed = offSet + int challengeScriptLength
      { Value = output
        ChallengeScriptLength = challengeScriptLength
        ChallengeScript = bytesToProcess.[offSet .. bytesUsed - 1] }, bytesUsed
  