X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=GHC%2FEnum.lhs;h=ac6e9a916a7d7967111d8776249dbee505c0ed77;hb=HEAD;hp=8441c765bc7ac603c779642d800367639c3911ca;hpb=10de2c656f74562b662c22928be85e1b3ccda796;p=ghc-base.git

diff --git a/GHC/Enum.lhs b/GHC/Enum.lhs
index 8441c76..ac6e9a9 100644
--- a/GHC/Enum.lhs
+++ b/GHC/Enum.lhs
@@ -1,5 +1,5 @@
 \begin{code}
-{-# OPTIONS_GHC -XNoImplicitPrelude #-}
+{-# LANGUAGE NoImplicitPrelude, BangPatterns, MagicHash #-}
 {-# OPTIONS_HADDOCK hide #-}
 -----------------------------------------------------------------------------
 -- |
@@ -350,62 +350,72 @@ instance  Enum Char  where
 -- We can do better than for Ints because we don't
 -- have hassles about arithmetic overflow at maxBound
 {-# INLINE [0] eftCharFB #-}
-eftCharFB c n x y = go x
+eftCharFB :: (Char -> a -> a) -> a -> Int# -> Int# -> a
+eftCharFB c n x0 y = go x0
                  where
                     go x | x ># y    = n
                          | otherwise = C# (chr# x) `c` go (x +# 1#)
 
-eftChar x y | x ># y    = [] 
-                | otherwise = C# (chr# x) : eftChar (x +# 1#) y
+eftChar :: Int# -> Int# -> String
+eftChar x y | x ># y    = []
+            | otherwise = C# (chr# x) : eftChar (x +# 1#) y
 
 
 -- For enumFromThenTo we give up on inlining
 {-# NOINLINE [0] efdCharFB #-}
+efdCharFB :: (Char -> a -> a) -> a -> Int# -> Int# -> a
 efdCharFB c n x1 x2
   | delta >=# 0# = go_up_char_fb c n x1 delta 0x10FFFF#
   | otherwise    = go_dn_char_fb c n x1 delta 0#
   where
-    delta = x2 -# x1
+    !delta = x2 -# x1
 
+efdChar :: Int# -> Int# -> String
 efdChar x1 x2
   | delta >=# 0# = go_up_char_list x1 delta 0x10FFFF#
   | otherwise    = go_dn_char_list x1 delta 0#
   where
-    delta = x2 -# x1
+    !delta = x2 -# x1
 
 {-# NOINLINE [0] efdtCharFB #-}
+efdtCharFB :: (Char -> a -> a) -> a -> Int# -> Int# -> Int# -> a
 efdtCharFB c n x1 x2 lim
   | delta >=# 0# = go_up_char_fb c n x1 delta lim
   | otherwise    = go_dn_char_fb c n x1 delta lim
   where
-    delta = x2 -# x1
+    !delta = x2 -# x1
 
+efdtChar :: Int# -> Int# -> Int# -> String
 efdtChar x1 x2 lim
   | delta >=# 0# = go_up_char_list x1 delta lim
   | otherwise    = go_dn_char_list x1 delta lim
   where
-    delta = x2 -# x1
+    !delta = x2 -# x1
 
-go_up_char_fb c n x delta lim
-  = go_up x
+go_up_char_fb :: (Char -> a -> a) -> a -> Int# -> Int# -> Int# -> a
+go_up_char_fb c n x0 delta lim
+  = go_up x0
   where
     go_up x | x ># lim  = n
             | otherwise = C# (chr# x) `c` go_up (x +# delta)
 
-go_dn_char_fb c n x delta lim
-  = go_dn x
+go_dn_char_fb :: (Char -> a -> a) -> a -> Int# -> Int# -> Int# -> a
+go_dn_char_fb c n x0 delta lim
+  = go_dn x0
   where
     go_dn x | x <# lim  = n
             | otherwise = C# (chr# x) `c` go_dn (x +# delta)
 
-go_up_char_list x delta lim
-  = go_up x
+go_up_char_list :: Int# -> Int# -> Int# -> String
+go_up_char_list x0 delta lim
+  = go_up x0
   where
     go_up x | x ># lim  = []
             | otherwise = C# (chr# x) : go_up (x +# delta)
 
-go_dn_char_list x delta lim
-  = go_dn x
+go_dn_char_list :: Int# -> Int# -> Int# -> String
+go_dn_char_list x0 delta lim
+  = go_dn x0
   where
     go_dn x | x <# lim  = []
             | otherwise = C# (chr# x) : go_dn (x +# delta)
@@ -443,7 +453,7 @@ instance  Enum Int  where
 
     {-# INLINE enumFrom #-}
     enumFrom (I# x) = eftInt x maxInt#
-        where I# maxInt# = maxInt
+        where !(I# maxInt#) = maxInt
         -- Blarg: technically I guess enumFrom isn't strict!
 
     {-# INLINE enumFromTo #-}
@@ -468,15 +478,15 @@ instance  Enum Int  where
 
 eftInt :: Int# -> Int# -> [Int]
 -- [x1..x2]
-eftInt x y | x ># y    = []
-           | otherwise = go x
+eftInt x0 y | x0 ># y    = []
+            | otherwise = go x0
                where
                  go x = I# x : if x ==# y then [] else go (x +# 1#)
 
 {-# INLINE [0] eftIntFB #-}
 eftIntFB :: (Int -> r -> r) -> r -> Int# -> Int# -> r
-eftIntFB c n x y | x ># y    = n        
-                 | otherwise = go x
+eftIntFB c n x0 y | x0 ># y    = n        
+                  | otherwise = go x0
                  where
                    go x = I# x `c` if x ==# y then n else go (x +# 1#)
                         -- Watch out for y=maxBound; hence ==, not >
@@ -518,8 +528,8 @@ efdtIntUp :: Int# -> Int# -> Int# -> [Int]
 efdtIntUp x1 x2 y    -- Be careful about overflow!
  | y <# x2   = if y <# x1 then [] else [I# x1]
  | otherwise = -- Common case: x1 <= x2 <= y
-               let delta = x2 -# x1 -- >= 0
-                   y' = y -# delta  -- x1 <= y' <= y; hence y' is representable
+               let !delta = x2 -# x1 -- >= 0
+                   !y' = y -# delta  -- x1 <= y' <= y; hence y' is representable
 
                    -- Invariant: x <= y
                    -- Note that: z <= y' => z + delta won't overflow
@@ -533,8 +543,8 @@ efdtIntUpFB :: (Int -> r -> r) -> r -> Int# -> Int# -> Int# -> r
 efdtIntUpFB c n x1 x2 y    -- Be careful about overflow!
  | y <# x2   = if y <# x1 then n else I# x1 `c` n
  | otherwise = -- Common case: x1 <= x2 <= y
-               let delta = x2 -# x1 -- >= 0
-                   y' = y -# delta  -- x1 <= y' <= y; hence y' is representable
+               let !delta = x2 -# x1 -- >= 0
+                   !y' = y -# delta  -- x1 <= y' <= y; hence y' is representable
 
                    -- Invariant: x <= y
                    -- Note that: z <= y' => z + delta won't overflow
@@ -548,8 +558,8 @@ efdtIntDn :: Int# -> Int# -> Int# -> [Int]
 efdtIntDn x1 x2 y    -- Be careful about underflow!
  | y ># x2   = if y ># x1 then [] else [I# x1]
  | otherwise = -- Common case: x1 >= x2 >= y
-               let delta = x2 -# x1 -- <= 0
-                   y' = y -# delta  -- y <= y' <= x1; hence y' is representable
+               let !delta = x2 -# x1 -- <= 0
+                   !y' = y -# delta  -- y <= y' <= x1; hence y' is representable
 
                    -- Invariant: x >= y
                    -- Note that: z >= y' => z + delta won't underflow
@@ -563,8 +573,8 @@ efdtIntDnFB :: (Int -> r -> r) -> r -> Int# -> Int# -> Int# -> r
 efdtIntDnFB c n x1 x2 y    -- Be careful about underflow!
  | y ># x2 = if y ># x1 then n else I# x1 `c` n
  | otherwise = -- Common case: x1 >= x2 >= y
-               let delta = x2 -# x1 -- <= 0
-                   y' = y -# delta  -- y <= y' <= x1; hence y' is representable
+               let !delta = x2 -# x1 -- <= 0
+                   !y' = y -# delta  -- y <= y' <= x1; hence y' is representable
 
                    -- Invariant: x >= y
                    -- Note that: z >= y' => z + delta won't underflow