anchor.diff:              | :? System.Collections.Generic.KeyNotFoundException -> None
   
           Assert.IsTrue((b = a))
  -    Check.Verbose <| testFun (fun e -> e % 3 = 2) 
  +    Check.VerboseThrowOnFailure <| testFun (fun e -> e % 3 = 2) 
   
   [<Test>]
   let ``Random ToArray``() =   
       let testFun (bra:BlockResizeArray<int>) =        
           let arr = bra.ToArray()
           compareByElems bra arr
  -    Check.Verbose <| testFun+    Check.VerboseThrowOnFailure <| testFun
positive.code:         let b = bra.Map f
          let a = Array.map f arr
          compareByElems b a
      Check.Verbose <| testFun (fun e -> e * 2)
      
  [<Test>]
  let ``Random filter``() =   
  
negative.code: let testIters = 10
  let x = 1000UL
  let testLen = 1000000
  let rand = System.Random()
  
  let compareByElems (bra : BlockResizeArray<'T>) (arr : 'T []) = 
      let mutable res = true 
  