diff options
| -rw-r--r-- | compiler/GHC/Builtin/Names.hs | 5 | ||||
| -rw-r--r-- | libraries/base/Data/Data.hs | 3 | ||||
| -rw-r--r-- | libraries/base/Data/Void.hs | 68 | ||||
| -rw-r--r-- | libraries/base/GHC/Base.hs | 38 | ||||
| -rw-r--r-- | libraries/base/GHC/Exception/Type.hs | 3 | ||||
| -rw-r--r-- | libraries/base/GHC/Generics.hs | 5 | ||||
| -rw-r--r-- | libraries/base/GHC/Ix.hs | 8 | ||||
| -rw-r--r-- | libraries/base/GHC/Read.hs | 6 | ||||
| -rw-r--r-- | libraries/base/GHC/Show.hs | 3 |
9 files changed, 69 insertions, 70 deletions
diff --git a/compiler/GHC/Builtin/Names.hs b/compiler/GHC/Builtin/Names.hs index a9802e3e95..acc402b4a3 100644 --- a/compiler/GHC/Builtin/Names.hs +++ b/compiler/GHC/Builtin/Names.hs @@ -547,7 +547,7 @@ gHC_PRIM, gHC_PRIM_PANIC, gHC_GHCI, gHC_GHCI_HELPERS, gHC_CSTRING, gHC_SHOW, gHC_READ, gHC_NUM, gHC_MAYBE, gHC_NUM_INTEGER, gHC_NUM_NATURAL, gHC_NUM_BIGNAT, - gHC_LIST, gHC_TUPLE, gHC_TUPLE_PRIM, dATA_EITHER, dATA_VOID, dATA_LIST, dATA_STRING, + gHC_LIST, gHC_TUPLE, gHC_TUPLE_PRIM, dATA_EITHER, dATA_LIST, dATA_STRING, dATA_FOLDABLE, dATA_TRAVERSABLE, gHC_CONC, gHC_IO, gHC_IO_Exception, gHC_ST, gHC_IX, gHC_STABLE, gHC_PTR, gHC_ERR, gHC_REAL, @@ -583,7 +583,6 @@ gHC_LIST = mkBaseModule (fsLit "GHC.List") gHC_TUPLE = mkPrimModule (fsLit "GHC.Tuple") gHC_TUPLE_PRIM = mkPrimModule (fsLit "GHC.Tuple.Prim") dATA_EITHER = mkBaseModule (fsLit "Data.Either") -dATA_VOID = mkBaseModule (fsLit "Data.Void") dATA_LIST = mkBaseModule (fsLit "Data.List") dATA_STRING = mkBaseModule (fsLit "Data.String") dATA_FOLDABLE = mkBaseModule (fsLit "Data.Foldable") @@ -964,7 +963,7 @@ leftDataConName = dcQual dATA_EITHER (fsLit "Left") leftDataConKey rightDataConName = dcQual dATA_EITHER (fsLit "Right") rightDataConKey voidTyConName :: Name -voidTyConName = tcQual dATA_VOID (fsLit "Void") voidTyConKey +voidTyConName = tcQual gHC_BASE (fsLit "Void") voidTyConKey -- Generics (types) v1TyConName, u1TyConName, par1TyConName, rec1TyConName, diff --git a/libraries/base/Data/Data.hs b/libraries/base/Data/Data.hs index 4ef7d00d03..b6102d4cf3 100644 --- a/libraries/base/Data/Data.hs +++ b/libraries/base/Data/Data.hs @@ -1187,6 +1187,9 @@ deriving instance Data Ordering -- | @since 4.0.0.0 deriving instance (Data a, Data b) => Data (Either a b) +-- | @since 4.8.0.0 +deriving instance Data Void + -- | @since 4.0.0.0 deriving instance Data () diff --git a/libraries/base/Data/Void.hs b/libraries/base/Data/Void.hs index 299b4c78bf..226a9ad994 100644 --- a/libraries/base/Data/Void.hs +++ b/libraries/base/Data/Void.hs @@ -1,8 +1,4 @@ -{-# LANGUAGE DeriveDataTypeable #-} -{-# LANGUAGE DeriveGeneric #-} -{-# LANGUAGE EmptyCase #-} -{-# LANGUAGE EmptyDataDeriving #-} -{-# LANGUAGE Safe #-} +{-# LANGUAGE Trustworthy #-} ----------------------------------------------------------------------------- -- | @@ -24,64 +20,4 @@ module Data.Void , vacuous ) where -import Control.Exception -import Data.Data -import Data.Ix -import GHC.Generics -import Data.Semigroup (Semigroup(..), stimesIdempotent) - --- $setup --- >>> import Prelude - --- | Uninhabited data type --- --- @since 4.8.0.0 -data Void deriving - ( Eq -- ^ @since 4.8.0.0 - , Data -- ^ @since 4.8.0.0 - , Generic -- ^ @since 4.8.0.0 - , Ord -- ^ @since 4.8.0.0 - , Read -- ^ Reading a 'Void' value is always a parse error, considering - -- 'Void' as a data type with no constructors. - -- - -- @since 4.8.0.0 - , Show -- ^ @since 4.8.0.0 - ) - --- | @since 4.8.0.0 -instance Ix Void where - range _ = [] - index _ = absurd - inRange _ = absurd - rangeSize _ = 0 - --- | @since 4.8.0.0 -instance Exception Void - --- | @since 4.9.0.0 -instance Semigroup Void where - a <> _ = a - stimes = stimesIdempotent - --- | Since 'Void' values logically don't exist, this witnesses the --- logical reasoning tool of \"ex falso quodlibet\". --- --- >>> let x :: Either Void Int; x = Right 5 --- >>> :{ --- case x of --- Right r -> r --- Left l -> absurd l --- :} --- 5 --- --- @since 4.8.0.0 -absurd :: Void -> a -absurd a = case a of {} - --- | If 'Void' is uninhabited then any 'Functor' that holds only --- values of type 'Void' is holding no values. --- It is implemented in terms of @fmap absurd@. --- --- @since 4.8.0.0 -vacuous :: Functor f => f Void -> f a -vacuous = fmap absurd +import GHC.Base (Void, absurd, vacuous) diff --git a/libraries/base/GHC/Base.hs b/libraries/base/GHC/Base.hs index 6cc195d362..ca815f246d 100644 --- a/libraries/base/GHC/Base.hs +++ b/libraries/base/GHC/Base.hs @@ -65,6 +65,8 @@ Other Prelude modules are much easier with fewer complex dependencies. {-# LANGUAGE BangPatterns #-} {-# LANGUAGE CPP #-} {-# LANGUAGE DataKinds #-} +{-# LANGUAGE EmptyCase #-} +{-# LANGUAGE EmptyDataDeriving #-} {-# LANGUAGE ExistentialQuantification #-} {-# LANGUAGE MagicHash #-} {-# LANGUAGE NoImplicitPrelude #-} @@ -199,6 +201,37 @@ build = errorWithoutStackTrace "urk" foldr = errorWithoutStackTrace "urk" #endif +-- | Uninhabited data type +-- +-- @since 4.8.0.0 +data Void deriving + ( Eq -- ^ @since 4.8.0.0 + , Ord -- ^ @since 4.8.0.0 + ) + +-- | Since 'Void' values logically don't exist, this witnesses the +-- logical reasoning tool of \"ex falso quodlibet\". +-- +-- >>> let x :: Either Void Int; x = Right 5 +-- >>> :{ +-- case x of +-- Right r -> r +-- Left l -> absurd l +-- :} +-- 5 +-- +-- @since 4.8.0.0 +absurd :: Void -> a +absurd a = case a of {} + +-- | If 'Void' is uninhabited then any 'Functor' that holds only +-- values of type 'Void' is holding no values. +-- It is implemented in terms of @fmap absurd@. +-- +-- @since 4.8.0.0 +vacuous :: Functor f => f Void -> f a +vacuous = fmap absurd + infixr 6 <> -- | The class of semigroups (types with an associative binary operation). @@ -328,6 +361,11 @@ instance Monoid [a] where mconcat xss = [x | xs <- xss, x <- xs] -- See Note: [List comprehensions and inlining] +-- | @since 4.9.0.0 +instance Semigroup Void where + a <> _ = a + stimes _ a = a + {- Note: [List comprehensions and inlining] ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ diff --git a/libraries/base/GHC/Exception/Type.hs b/libraries/base/GHC/Exception/Type.hs index 642e1a9889..7f915b0c5a 100644 --- a/libraries/base/GHC/Exception/Type.hs +++ b/libraries/base/GHC/Exception/Type.hs @@ -143,6 +143,9 @@ class (Typeable e, Show e) => Exception e where displayException :: e -> String displayException = show +-- | @since 4.8.0.0 +instance Exception Void + -- | @since 3.0 instance Exception SomeException where toException se = se diff --git a/libraries/base/GHC/Generics.hs b/libraries/base/GHC/Generics.hs index 66ee8ba300..d020bc7b32 100644 --- a/libraries/base/GHC/Generics.hs +++ b/libraries/base/GHC/Generics.hs @@ -746,7 +746,7 @@ import GHC.Types import GHC.Ix ( Ix ) import GHC.Base ( Alternative(..), Applicative(..), Functor(..) , Monad(..), MonadPlus(..), NonEmpty(..), String, coerce - , Semigroup(..), Monoid(..) ) + , Semigroup(..), Monoid(..), Void ) import GHC.Classes ( Eq(..), Ord(..) ) import GHC.Enum ( Bounded, Enum ) import GHC.Read ( Read(..) ) @@ -1553,6 +1553,9 @@ data Meta = MetaData Symbol Symbol Symbol Bool -- Derived instances -------------------------------------------------------------------------------- +-- | @since 4.8.0.0 +deriving instance Generic Void + -- | @since 4.6.0.0 deriving instance Generic [a] diff --git a/libraries/base/GHC/Ix.hs b/libraries/base/GHC/Ix.hs index abbe62c2f1..27cd703e42 100644 --- a/libraries/base/GHC/Ix.hs +++ b/libraries/base/GHC/Ix.hs @@ -273,6 +273,14 @@ instance Ix Ordering where -- as derived inRange (l,u) i = fromEnum i >= fromEnum l && fromEnum i <= fromEnum u ---------------------------------------------------------------------- +-- | @since 4.8.0.0 +instance Ix Void where + range _ = [] + index _ = absurd + inRange _ = absurd + rangeSize _ = 0 + +---------------------------------------------------------------------- -- | @since 2.01 instance Ix () where {-# INLINE range #-} diff --git a/libraries/base/GHC/Read.hs b/libraries/base/GHC/Read.hs index 2c9aec08cd..75ccb0c5da 100644 --- a/libraries/base/GHC/Read.hs +++ b/libraries/base/GHC/Read.hs @@ -656,6 +656,12 @@ instance (Integral a, Read a) => Read (Ratio a) where -- Tuple instances of Read, up to size 15 ------------------------------------------------------------------------ +-- | Reading a 'Void' value is always a parse error, considering +-- 'Void' as a data type with no constructors. +-- +-- @since 4.8.0.0 +deriving instance Read Void + -- | @since 2.01 instance Read () where readPrec = diff --git a/libraries/base/GHC/Show.hs b/libraries/base/GHC/Show.hs index 04fbcb6112..0d3f1a926d 100644 --- a/libraries/base/GHC/Show.hs +++ b/libraries/base/GHC/Show.hs @@ -165,6 +165,9 @@ appPrec1 = I# 11# -- appPrec + 1 -- Simple Instances -------------------------------------------------------------- +-- | @since 4.8.0.0 +deriving instance Show Void + -- | @since 2.01 deriving instance Show () |