[clean-list] Exercise 2 from Chapter 2 of Clean Book

fzuurbie@inter.nl.net fzuurbie@inter.nl.net
Thu, 20 Nov 2003 07:49:56 UT


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> Howdy,
> 
> The problem is...
> 
>    Finite precision of reals. Execute the start expression given
>    in section 2.4.2.  Rewrite the program such that it only prints
>    the smallest number that is different from zero using the
>    function until.
> 
> The program we must rewrite is...
> 
>    Start = takeWhile ((<>) 0.0) (iterate (\x -> x/10.0) 1.0)
[...]
> Can anyone help me with this?
> 

Yes: never use == (or <> for that matter) on Reals

The Nijmegen team should consider removing the == instance for Reals

For now: skip the exercise, it should never have been in the book in the first place.

Regards Erik Zuurbier



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