anchor.diff:  
   [<Test>]
   let ``while``() = 
  -    let i = ref 10    
  -    let task = Task.TaskBuilder(continuationOptions = TaskContinuationOptions.ExecuteSynchronously)
  +    let i = ref 10        
       let t() =
           task {
               while !i > 0 do
  
positive.code: 
  
  [<Test>]
  let ``try with should catch exception in the body``() =
     let task = Task.TaskBuilder(continuationOptions = TaskContinuationOptions.ExecuteSynchronously)
     let result = task {
        try 
           failwith "exception"
  
negative.code: 
  
  [<Test>]
  let ``try with should do unwrapping of exception to original type if it was raised in continuation``() =   
     let result = task {
        try 
           do! Task.Factory.StartNew(fun () -> invalidArg "param name" "msg")
  