anchor.diff:                      env.Write s1
                       env.Write("%")
                       env.Write s2
  -                    env.Finalize()
  +                    env.Finish()
                   )
               )
   
  
positive.code:                     env.Write s1
                      env.WriteT(f env.State a)
                      env.Write s2
                      env.Finalize()
                  )
              )
          static member LittleAChained<'A, 'Tail>(s1 : string, next : PrintfFactory<'State, 'Residue, 'Result,'Tail>) = 
  
negative.code:         let buf : string[] = Array.zeroCreate n
          let mutable ptr = 0
  
          override __.Finish() : 'Result = k (String.Concat(buf))
          override __.Write(s : string) = 
              buf.[ptr] <- s
              ptr <- ptr + 1
  