[Haskell-cafe] Re: map (-2) [1..5]

Ross Paterson ross at soi.city.ac.uk
Sat Sep 9 08:45:26 EDT 2006

On Sat, Sep 09, 2006 at 12:57:56AM -0400, Cale Gibbard wrote:
> Num itself needs to be split, but we can't do it sanely without
> something like class aliases.

I think that a finer grain numeric hierarchy, while retaining Num, etc,
is feasible without changing the language: unlike the case of monads,
the people who will be defining instances of numeric classes are the
very ones who are inconvenienced by the current hierarchy.  The main
impact on clients of the classes is that some functions would have
more general types.

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