anchor.diff:                      // note loop bounds
                       for q in start .. (stop-1) do
                           let k = snd children.[q]
  -                        match overflows.TryFind(q) with
  +                        match overflows.TryFind(k) with
                           | Some pg ->
                               pb.PutByte(FLAG_OVERFLOW)
                               pb.PutVarint(int64 k.Length)
  
positive.code:                             else
                                  let keyOverflowFirstPage = nextPageNumber
                                  let kRange = writeOverflow nextPageNumber boundaryPageNumber (new MemoryStream(k))
                                  {args with sofar=sofar + neededForOverflow; nextPage=fst kRange; boundaryPage=snd kRange; overflows=overflows.Add(i,keyOverflowFirstPage)}
  
  
                      // this is the body of the folder function
  
negative.code:             nextPage:int; 
              boundaryPage:int; 
              //children:(int32*byte[]); 
              overflows:Map<byte[],int32>;
          }
  
      let Create(fs:Stream, pageManager:IPages, csr:ICursor) :int32 = 
  