I've just started reading Jon Harrop's F# Journal (I'm impressed so far, BTW):

[link:www.ffconsultancy.com]

In the article "The Essence Functional Programming" he gives a nice example of a timer function:

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> let time f x =
    let t = new System.Diagnostics.Stopwatch()
    t.Start()

    let f_x = f x
    printf "%fs\n" (Float.of_int64 t.ElapsedMilliseconds / 1e3)
    f_x;;

val time : ('a -> 'b) -> 'a -> 'b

The problem is that I can't even type this into FSI:

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> let time f x =
let t = new System.Diagnostics.Stopwatch()
t.Start()

t.Start()
----^^
stdin(9,4): error: syntax error.
> 

I'm running Windows XP SP2, F# Version 1.9.3.14, and I'm using the free Microsoft Visual Studio 2008 shell. Here's the info from Visual Studio:
Version 9.0.21022.8 RTM
Microsoft .NET Framework
Version 3.5 Installed Edition: IDE Standard

F# Research Compiler with Visual Studio 2003/2005 Integration 1.1
F# Research Compiler with Visual Studio 2003/2005 Integration. For more information about F#, see the Microsoft Research website at <[link:research.microsoft.com]>. F# Copyright 2001-2005 Microsoft Corporation.

I get the same error if I try to type it in FSI from cmd.exe.

On my laptop, the example works in VS 2005 with the same version of F#.

On page 50 of "Expert F#" there is a similar time function and it gives similar results.

Any ideas?

Thanks,

Dan