State of DData

Robert Will robertw at
Fri Apr 2 10:39:19 EST 2004

On Fri, 26 Mar 2004, Wolfgang Jeltsch wrote:
> Hmm, than we have a different interpretation of the standard as far as
> (==) is concerned.  Well, concerning Monad you're probably right because
> the Report only says "should" satisfy instead of "shall" satisfy or
> whatever.  As far as I could see the Report says nothing about the
> meaning of (+).

Well, the next version of Haskell with Design by Contract will of course
formally specify all those laws, so I won't be forced any more to pay
attention to the difference between "shall" and "should".  The sense of
the latter being surely questionable, since a law that doesn't always
hold, is not a law, but a hidden bug.

It may seem a bit late that FP now gets, what has been into imperative
practice in 1985.  (Bibliography on )


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