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TryFsharp.org create appears to be out of date RRS feed

  • Question

  • Phillip Carter did a demo at build (I'm watching the recording-Binary Search Tree) which was this

    type BST<'T> =
        |Empty
        |Node of value:'T*left:BST<'T> * right:BST<'T>
    
    let rec flip bst =
        match bst with
        | Empty -> bst
        |Node(x,left,right)-> Node(x, flip right, flip left)
    
    [<EntryPoint>]
    let main argv =
        let bst = Node(4, Node(3, Empty,Empty), Node(5,Empty,Empty))
        let flipped = flip bst
        
        prntfn "BST: %A \nFlipped: %A\n\n" bst flipped
        0

    The code shows errors in the bold code above. When I try to run the code, this is what I get

    Welcome to Try F# 3.0
    For additional help: http://www.tryfsharp.org/Help


    type BST<'T> =
          |Empty
          |Node of value: 'T*left:BST<'T> * right:BST<'T>
      
      let rec flip bst =
          match bst with
          | Empty -> bst
          |Node(x,left,right)-> Node(x, flip right, flip left)
      
      [<EntryPoint>]
      [... and 7 more line(s)]
          |Node of value: 'T*left:BST<'T> * right:BST<'T>
      ------------------^

    stdin(3,19): error FS0010: Unexpected symbol ':' in member definition

    So, Is the website using VS2012 F# and more up to date code won't work? The code did work in his demo but not here.

    Thanks

    Wednesday, August 8, 2018 4:50 PM