guid.fs

    [<Inline "$v.toString(16)">]
    let toHex (v: int) = X<_>

    let guid() =
        let rx = EcmaScript.RegExp("[xy]", "g")
        EcmaScript.String("xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx").Replace(rx, As (fun c ->
            let r = EcmaScript.Math.Random() * 16.0 |> int
            let v =
                match c with
                | 'x' -> r
                | _ -> r &&& 0x3 ||| 0x8
            toHex v
        ))