anchor.diff:  module WebSharper.Tests.Seq
   
   open WebSharper
  +open WebSharper.JavaScript
   open WebSharper.Testing
   module R = WebSharper.Testing.Random
         
  
positive.code:             equal (Seq.scanBack (+) { 1 .. 10 } 9 |> Array.ofSeq) [| 64; 63; 61; 58; 54; 49; 43; 36; 28; 19; 9 |]
          }
  
          Test "Seq.sortWith" {                                                                   
              equal (Seq.sortWith (fun a b -> compare (a % 3) (b % 3)) { 0 .. 10 } |> Array.ofSeq) [| 0; 3; 6; 9; 1; 4; 7; 10; 2; 5; 8 |]
          }
  
          #endif
  
negative.code:         Test "Seq.sort" {
              equal (Seq.sort [| 1; 8; -5; 2 |] |> Seq.toArray)
                  [| -5; 1; 2; 8 |]
              property (fun x -> Do {
                  let s = Seq.sort x
                  isTrueMsg (isPermutation s x) "Result is a permutation of original"
                  isTrueMsg (s |> Seq.pairwise |> Seq.forall (fun (x, y) -> x <= y)) "Result is sorted"
              })
          }
  
          Test "Seq.sortBy" {
              let f = fun x -> 10 - x
              let s = Seq.sortBy f [6;7;8;9;10]
              equal (Seq.toArray s) [|10;9;8;7;6|]
              property (fun x -> Do {
                  let s = Seq.sortBy f x
                  isTrueMsg (isPermutation s x) "Result is a permutation of original"
                  isTrueMsg (s |> Seq.pairwise |> Seq.forall (fun (x, y) -> f x <= f y)) "Result is sorted"
              })
          }
  
          Test "Seq.sum" {
  