A sample revised prelude for numeric classes

[Marcin 'Qrczak' Kowalczyk]

Mon, 12 Feb 2001 12:04:39 +0100 (CET), Marcin 'Qrczak' Kowalczyk <mk167280@zodiac.mimuw.edu.pl> pisze:

> This is my bet.

I changed my mind:

    class Eq a => PartialOrd a where -- or Ord
        (<), (>), (<=), (>=) :: a -> a -> Bool
        -- Minimal definition: (<) or (<=).
        -- For partial order (<=) is required.
        -- For total order (<) is recommended for efficiency.
        a < b  = a <= b && a /= b
        a > b  = b < a
        a <= b = not (b < a)
        a >= b = b <= a

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 __("<  Marcin Kowalczyk * qrczak@knm.org.pl http://qrczak.ids.net.pl/
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