X-Git-Url: http://git.megacz.com/?p=ghc-hetmet.git;a=blobdiff_plain;f=compiler%2FbasicTypes%2FUnique.lhs;h=aecd37219790545cce74339e7945f9d7f745c40e;hp=51907028e5d69e18276778c4627da83f7abceff3;hb=831a35dd00faff195cf938659c2dd736192b865f;hpb=e415eeaf6c7771488af24758ca5b9c22c42be3a6

diff --git a/compiler/basicTypes/Unique.lhs b/compiler/basicTypes/Unique.lhs
index 5190702..aecd372 100644
--- a/compiler/basicTypes/Unique.lhs
+++ b/compiler/basicTypes/Unique.lhs
@@ -17,7 +17,11 @@ Haskell).
 
 \begin{code}
 module Unique (
-	Unique, Uniquable(..), hasKey,
+        -- * Main data types
+	Unique, Uniquable(..), 
+	
+	-- ** Constructors, desctructors and operations on 'Unique's
+	hasKey,
 
 	pprUnique, 
 
@@ -32,6 +36,8 @@ module Unique (
 
 	isTupleKey, 
 
+        -- ** Making built-in uniques
+
 	-- now all the built-in Uniques (and functions to make them)
 	-- [the Oh-So-Wonderful Haskell module system wins again...]
 	mkAlphaTyVarUnique,
@@ -54,9 +60,7 @@ import BasicTypes
 import FastTypes
 import FastString
 import Outputable
-#ifdef DEBUG
-import StaticFlags	( opt_SuppressUniques )
-#endif
+import StaticFlags
 
 #if defined(__GLASGOW_HASKELL__)
 --just for implementing a fast [0,61) -> Char function
@@ -78,6 +82,10 @@ Fast comparison is everything on @Uniques@:
 
 \begin{code}
 --why not newtype Int?
+
+-- | The type of unique identifiers that are used in many places in GHC
+-- for fast ordering and equality tests. You should generate these with
+-- the functions from the 'UniqSupply' module
 data Unique = MkUnique FastInt
 \end{code}
 
@@ -126,8 +134,8 @@ newTagUnique u c = mkUnique c i where (_,i) = unpkUnique u
 mkUnique c i
   = MkUnique (tag `bitOrFastInt` bits)
   where
-    tag  = fastOrd (cUnbox c) `shiftLFastInt` _ILIT(24)
-    bits = iUnbox i `bitAndFastInt` _ILIT(16777215){-``0x00ffffff''-}
+    !tag  = fastOrd (cUnbox c) `shiftLFastInt` _ILIT(24)
+    !bits = iUnbox i `bitAndFastInt` _ILIT(16777215){-``0x00ffffff''-}
 
 unpkUnique (MkUnique u)
   = let
@@ -148,6 +156,7 @@ unpkUnique (MkUnique u)
 %************************************************************************
 
 \begin{code}
+-- | Class of things that we can obtain a 'Unique' from
 class Uniquable a where
     getUnique :: a -> Unique
 
@@ -202,11 +211,9 @@ We do sometimes make strings with @Uniques@ in them:
 \begin{code}
 pprUnique :: Unique -> SDoc
 pprUnique uniq
-#ifdef DEBUG
   | opt_SuppressUniques
   = empty	-- Used exclusively to suppress uniques so you 
   | otherwise	-- can compare output easily
-#endif
   = case unpkUnique uniq of
       (tag, u) -> finish_ppr tag u (text (iToBase62 u))
 
@@ -259,7 +266,7 @@ iToBase62 n_
 #if defined(__GLASGOW_HASKELL__)
     --then FastInt == Int#
     chooseChar62 n = C# (indexCharOffAddr# chars62 n)
-    chars62 = "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ"#
+    !chars62 = "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ"#
 #else
     --Haskell98 arrays are portable
     chooseChar62 n = (!) chars62 n
@@ -280,6 +287,8 @@ Allocation of unique supply characters:
 	X:   uniques derived by deriveUnique
 	_:   unifiable tyvars   (above)
 	0-9: prelude things below
+	     (no numbers left any more..)
+	::   (prelude) parallel array data constructors
 
 	other a-z: lower case chars for unique supplies.  Used so far:
 
@@ -328,8 +337,8 @@ mkTupleDataConUnique Unboxed a	= mkUnique '8' (2*a)
 isTupleKey u = case unpkUnique u of
 		(tag,_) -> tag == '4' || tag == '5' || tag == '7' || tag == '8'
 
-mkPrimOpIdUnique op		= mkUnique '9' op
-mkPreludeMiscIdUnique i		= mkUnique '0' i
+mkPrimOpIdUnique op         = mkUnique '9' op
+mkPreludeMiscIdUnique  i    = mkUnique '0' i
 
 -- No numbers left anymore, so I pick something different for the character
 -- tag