diff options
Diffstat (limited to 'libraries/base/GHC/Base.hs')
| -rw-r--r-- | libraries/base/GHC/Base.hs | 9 |
1 files changed, 7 insertions, 2 deletions
diff --git a/libraries/base/GHC/Base.hs b/libraries/base/GHC/Base.hs index 2d6e0e4195..35de446ca6 100644 --- a/libraries/base/GHC/Base.hs +++ b/libraries/base/GHC/Base.hs @@ -83,6 +83,7 @@ Other Prelude modules are much easier with fewer complex dependencies. , UnboxedTuples , ExistentialQuantification , RankNTypes + , KindSignatures #-} -- -Wno-orphans is needed for things like: -- Orphan rule: "x# -# x#" ALWAYS forall x# :: Int# -# x# x# = 0 @@ -1287,9 +1288,13 @@ flip f x y = f y x -- -- It is also useful in higher-order situations, such as @'map' ('$' 0) xs@, -- or @'Data.List.zipWith' ('$') fs xs@. +-- +-- Note that @($)@ is levity-polymorphic in its result type, so that +-- foo $ True where foo :: Bool -> Int# +-- is well-typed {-# INLINE ($) #-} -($) :: (a -> b) -> a -> b -f $ x = f x +($) :: forall r a (b :: TYPE r). (a -> b) -> a -> b +f $ x = f x -- | Strict (call-by-value) application operator. It takes a function and an -- argument, evaluates the argument to weak head normal form (WHNF), then calls |