{-| Copyright : (C) 2019, QBayLogic License : BSD2 (see the file LICENSE) Maintainer : Christiaan Baaij -} {-# LANGUAGE CPP #-} {-# LANGUAGE FlexibleContexts #-} {-# OPTIONS_GHC -fplugin=GHC.TypeLits.Extra.Solver #-} {-# OPTIONS_GHC -fplugin=GHC.TypeLits.Normalise #-} {-# OPTIONS_GHC -fplugin=GHC.TypeLits.KnownNat.Solver #-} {-# OPTIONS_HADDOCK show-extensions #-} #include "MachDeps.h" module Clash.Class.Parity ( Parity (..) ) where import Prelude hiding (even, odd) import Data.Int import Data.Word import Foreign.C.Types (CUShort) import GHC.TypeLits (KnownNat) import Clash.Class.BitPack (pack) import Clash.Sized.Internal.BitVector (BitVector, high, low, lsb#) import Clash.Promoted.Nat (SNat(..), snatToNum) {- \$setup >>> :m -Prelude >>> import Clash.Prelude >>> import Clash.Class.Parity -} -- | Determine whether value is odd or even class Parity a where -- | Check if value is even -- -- >>> even (4 :: Unsigned 4) -- True even :: a -> Bool even = not . odd -- | Check if value is odd -- -- >>> odd (4 :: Unsigned 4) -- False odd :: a -> Bool odd = not . even {-# MINIMAL even | odd #-} instance Parity Integer where even a = a `mod` 2 == 0 odd a = a `mod` 2 == 1 instance KnownNat n => Parity (BitVector n) where even a = case snatToNum @Integer (SNat @n) of 0 -> True _ -> (==low) \$ lsb# a odd a = case snatToNum @Integer (SNat @n) of 0 -> False _ -> (==high) \$ lsb# a instance Parity Bool where even = even . pack odd = odd . pack instance Parity CUShort where even = even . pack odd = odd . pack instance Parity Word where even = even . pack odd = odd . pack instance Parity Word8 where even = even . pack odd = odd . pack instance Parity Word16 where even = even . pack odd = odd . pack instance Parity Word32 where even = even . pack odd = odd . pack instance Parity Word64 where even = even . pack odd = odd . pack instance Parity Int where even = even . pack odd = odd . pack instance Parity Int8 where even = even . pack odd = odd . pack instance Parity Int16 where even = even . pack odd = odd . pack instance Parity Int32 where even = even . pack odd = odd . pack instance Parity Int64 where even = even . pack odd = odd . pack