anchor.diff:          ()       // 8
   """
       => [ 2, 10,  8, 10
  -         3,  4,  4, 10
            3, 13,  4, 10
  -         6,  4,  8, 10 ]
  +         6,  6,  8, 10 ]
   
   [<Test>]
   let ``complex outlining test``() =
  
positive.code:     printfn "allo"
      printfn "allo"
  """
      =>  [(2, 0, 4, 18)]
  
  
  [<Test>]   
  
negative.code: | 0 ->  ()
          ()
  """
      => [ 2, 8, 4, 10
           (3, 2, 4, 10)]
  
  [<Test>]
  