> Note that the Haskell report does not require IEEE 754 binary encodings.
> In fact, it permits 'Float' to be a decimal floating point type.

True. Although I don't really understand why? Or rather, I don't understand why it can't be at least slightly more specific and at least state that Float is a 32-bit floating point value and Double is a 64-bit floating point value. The exact handling of various exceptions and denormals tends to vary across hardware, but this at least allows you to get at the representation.

I realise it'll be platform-specific (assuming isIEEE returns false), but then so is the behaviour of your code if you don't require IEEE support. 

ta,
Sam