ANNOUNCE: yap-0.0 - yet another prelude

Paterson, Ross R.Paterson at
Fri Aug 12 01:03:29 CEST 2011

wren ng thornton [wren at] writes:
> On 8/10/11 9:53 AM, Paterson, Ross wrote:
> > Yet another restructuring of the Prelude numeric classes on algebraic lines, proposed for a revision of the Haskell Prelude:
> >
> >
> Very nice in its simplicity, but it suffers from the same problem as all
> the other attempts I've seen. Namely it ignores the importance of
> semirings and runs headlong towards fields and beyond. The {(-), abs,
> signum, negate} methods really must be broken out from (+).

abs and signum are already split off, but it could be further split, with
Monoid and Semiring subclasses of AbelianGroup and Ring, and that
would fit nicely with a Natural type.  I wasn't sure it was worth it
(having + operate on lists might be confusing for beginners).
But this scheme doesn't preclude doing that later.

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