anchor.diff:              if !c > 100 then None else // prevent infinity seqs
               c := !c + 1
               f x
  -
  -    
       let s : 'b [] = Seq.unfold (f()) start |> Seq.toArray
       let l = List.unfold (f()) start |> List.toArray
       let a = Array.unfold (f()) start
  
positive.code:     let s = run (fun () -> xs |> Seq.find predicate)
      let l = run (fun () -> xs |> List.ofArray |> List.find predicate)
      let a = run (fun () -> xs |> Array.find predicate)
      consistency "filter" s l a
  
  [<Test>]
  let ``find is consistent`` () =
  
negative.code:     Check.QuickThrowOnFailure splitAt<NormalFloat>
  
  let splitInto<'a when 'a : equality> (xs : 'a []) count =
      let ls = List.ofArray xs
      if count < 1 then 
          Prop.throws<ArgumentException,_> (lazy List.splitInto count ls) .&.
          Prop.throws<ArgumentException,_> (lazy Array.splitInto count xs) .&.
          Prop.throws<ArgumentException,_> (lazy Seq.splitInto count xs) 
      else
          let s = run (fun () -> xs |> Seq.splitInto count |> Seq.map Seq.toArray |> Seq.toArray)
          let l = run (fun () -> ls |> List.splitInto count |> Seq.map Seq.toArray |> Seq.toArray)
          let a = run (fun () -> xs |> Array.splitInto count |> Seq.map Seq.toArray |> Seq.toArray)
          consistency "splitInto" s l a
  
  [<Test>]
  let ``splitInto is consistent`` () =
  