Haskell Report (again)

[Dylan Thurston]

On Fri, Jul 20, 2001 at 08:35:13AM -0700, Simon Peyton-Jones wrote:
> | (b) What is the code supposed to do?  The code you posted always
> |     prints a decimal point; I imagine this is intended?  Can this be
> |     documented?
> Sigh.  The numeric library is entirely inadequately documented.
> I suppose that now you have forced me to face up to this fact I shall
> have to write some (brief) documentation for at least the exported
> functions.

I could do it, if you prefer.

> | (c) I don't think the case e=0 is right; you miss the initial "0".
> True.  The e>=0 should be e>0, I think.

Yes, that should fix it.

> | (d) "floatToDigits" seems to return an exponent that is off by 1 from
> |     what I expected at first.  This is reasonable, but since the
> |     function is exported, it should be documented.
> 
> Here's a comment I've just deduced and typed in for floatToDigits.
> Does it meet the need?
> 
> -- floatToDigits takes a base and a non-negative RealFloat number,
> -- and returns a list of digits and an exponent. 
> -- In particular, if x>=0, and
> --	floatToDigits base x = ([d1,d2,...,dn], e)
> -- then
> --	(a) n >= 1
> --	(b) x = 0.d1d2...dn * (base**e)
> -- 	(c) 0 <= di <= base-1

Looks great!

--Dylan