diff options
Diffstat (limited to 'libraries/base/GHC/Enum.hs')
| -rw-r--r-- | libraries/base/GHC/Enum.hs | 30 |
1 files changed, 13 insertions, 17 deletions
diff --git a/libraries/base/GHC/Enum.hs b/libraries/base/GHC/Enum.hs index 70a964f6d3..54d6c6b34a 100644 --- a/libraries/base/GHC/Enum.hs +++ b/libraries/base/GHC/Enum.hs @@ -33,7 +33,7 @@ module GHC.Enum( import GHC.Base hiding ( many ) import GHC.Char -import GHC.Integer +import GHC.Num.Integer import GHC.Num import GHC.Show default () -- Double isn't available yet @@ -842,8 +842,8 @@ efdtWordDnFB c n x1 x2 y -- Be careful about underflow! instance Enum Integer where succ x = x + 1 pred x = x - 1 - toEnum (I# n) = smallInteger n - fromEnum n = I# (integerToInt n) + toEnum (I# n) = IS n + fromEnum n = integerToInt n -- See Note [Stable Unfolding for list producers] {-# INLINE enumFrom #-} @@ -961,29 +961,25 @@ dn_list x0 delta lim = go (x0 :: Integer) -- | @since 4.8.0.0 instance Enum Natural where - succ n = n `plusNatural` wordToNaturalBase 1## - pred n = n `minusNatural` wordToNaturalBase 1## + succ n = n + 1 + pred n = n - 1 + toEnum i + | i >= 0 = naturalFromIntUnsafe i + | otherwise = errorWithoutStackTrace "toEnum: unexpected negative Int" - toEnum = intToNatural - -#if defined(MIN_VERSION_integer_gmp) - -- This is the integer-gmp special case. The general case is after the endif. - fromEnum (NatS# w) + fromEnum (NS w) | i >= 0 = i | otherwise = errorWithoutStackTrace "fromEnum: out of Int range" where i = I# (word2Int# w) -#endif - fromEnum n = fromEnum (naturalToInteger n) - - enumFrom x = enumDeltaNatural x (wordToNaturalBase 1##) + fromEnum n = fromEnum (integerFromNatural n) + enumFrom x = enumDeltaNatural x 1 enumFromThen x y | x <= y = enumDeltaNatural x (y-x) - | otherwise = enumNegDeltaToNatural x (x-y) (wordToNaturalBase 0##) - - enumFromTo x lim = enumDeltaToNatural x (wordToNaturalBase 1##) lim + | otherwise = enumNegDeltaToNatural x (x-y) 0 + enumFromTo x lim = enumDeltaToNatural x 1 lim enumFromThenTo x y lim | x <= y = enumDeltaToNatural x (y-x) lim | otherwise = enumNegDeltaToNatural x (x-y) lim |