module GHC.Exts
(
-- * Representations of some basic types
- Int(..),Word(..),Float(..),Double(..),Integer(..),Char(..),
- Ptr(..), FunPtr(..),
+ Int(..),Word(..),Float(..),Double(..),
+ Char(..),
+ Ptr(..), FunPtr(..),
+
+ -- * The maximum tuple size
+ maxTupleSize,
-- * Primitive operations
module GHC.Prim,
- shiftL#, shiftRL#, iShiftL#, iShiftRA#, iShiftRL#,
+ shiftL#, shiftRL#, iShiftL#, iShiftRA#, iShiftRL#,
uncheckedShiftL64#, uncheckedShiftRL64#,
uncheckedIShiftL64#, uncheckedIShiftRA64#,
- -- * Fusion
- build, augment,
+ -- * Fusion
+ build, augment,
- -- * Overloaded string literals
- IsString(..),
+ -- * Overloaded string literals
+ IsString(..),
- -- * Debugging
- breakpoint, breakpointCond,
+ -- * Debugging
+ breakpoint, breakpointCond,
- -- * Ids with special behaviour
- lazy, inline,
+ -- * Ids with special behaviour
+ lazy, inline,
-- * Transform comprehensions
- Down(..), groupWith, sortWith, the
+ Down(..), groupWith, sortWith, the,
+
+ -- * Event logging
+ traceEvent
) where
import GHC.Prim
import GHC.Base
+import GHC.Magic
import GHC.Word
import GHC.Int
-import GHC.Num
-import GHC.Float
+-- import GHC.Float
import GHC.Ptr
import Data.String
import Data.List
+import Foreign.C
+
+-- XXX This should really be in Data.Tuple, where the definitions are
+maxTupleSize :: Int
+maxTupleSize = 62
-- | The 'Down' type allows you to reverse sort order conveniently. A value of type
-- @'Down' a@ contains a value of type @a@ (represented as @'Down' a@).
-- | 'the' ensures that all the elements of the list are identical
-- and then returns that unique element
the :: Eq a => [a] -> a
-the (x:xs)
+the (x:xs)
| all (x ==) xs = x
| otherwise = error "GHC.Exts.the: non-identical elements"
the [] = error "GHC.Exts.the: empty list"
groupWith f xs = build (\c n -> groupByFB c n (\x y -> f x == f y) (sortWith f xs))
groupByFB :: ([a] -> lst -> lst) -> lst -> (a -> a -> Bool) -> [a] -> lst
-groupByFB c n eq xs = groupByFBCore xs
+groupByFB c n eq xs0 = groupByFBCore xs0
where groupByFBCore [] = n
groupByFBCore (x:xs) = c (x:ys) (groupByFBCore zs)
where (ys, zs) = span (eq x) xs
+
+-- -----------------------------------------------------------------------------
+-- tracing
+
+traceEvent :: String -> IO ()
+traceEvent msg = do
+ withCString msg $ \(Ptr p) -> IO $ \s ->
+ case traceEvent# p s of s' -> (# s', () #)