Data/Poset/Instances.hs

   1 {-
   2  - Copyright (C) 2009-2010 Nick Bowler.
   3  -
   4  - License BSD2:  2-clause BSD license.  See LICENSE for full terms.
   5  - This is free software: you are free to change and redistribute it.
   6  - There is NO WARRANTY, to the extent permitted by law.
   7  -}
   8
   9 -- | 'Poset' and 'Sortable' instances for instances of 'Prelude.Ord'
  10 {-# LANGUAGE CPP #-}
  11 module Data.Poset.Instances where
  12
  13 import qualified Data.Poset.Internal as Poset
  14 import Data.Poset.Internal (Poset, Sortable, partialOrder, totalOrder)
  15
  16 import Data.Ratio
  17 import Data.List
  18 import Data.Word
  19 import Data.Int
  20
  21 #define POSET_ORD_INSTANCE(ctx, v) instance ctx Poset (v) where { \
  22     compare = (partialOrder .) . compare; \
  23     (<)     = (<); \
  24     (<=)    = (<=); \
  25     (>=)    = (>=); \
  26     (>)     = (>); \
  27     (<==>)  = const $ const True; \
  28     (</=>)  = const $ const False }
  29
  30 #define SORTABLE_ORD_INSTANCE(ctx, v) instance ctx Sortable (v) where { \
  31     isOrdered = const True; \
  32     sortBy f = sortBy $ (totalOrder .) . f; \
  33     max    = max; \
  34     min    = min; }
  35
  36 #define ORD_INSTANCE(ctx, v) \
  37     POSET_ORD_INSTANCE(ctx, v); \
  38     SORTABLE_ORD_INSTANCE(ctx, v); \
  39     instance ctx Poset.Ord (v)
  40
  41 ORD_INSTANCE(, Bool)
  42 ORD_INSTANCE(, Char)
  43 ORD_INSTANCE(, Int)
  44 ORD_INSTANCE(, Int8)
  45 ORD_INSTANCE(, Int16)
  46 ORD_INSTANCE(, Int32)
  47 ORD_INSTANCE(, Int64)
  48 ORD_INSTANCE(, Word)
  49 ORD_INSTANCE(, Word8)
  50 ORD_INSTANCE(, Word16)
  51 ORD_INSTANCE(, Word32)
  52 ORD_INSTANCE(, Word64)
  53 ORD_INSTANCE(, Integer)
  54
  55 ORD_INSTANCE(Integral a =>, Ratio a)