X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=ghc%2Fcompiler%2FbasicTypes%2FUniqSupply.lhs;h=218df9ee9034801e89d6b562b98978f6fa75ae07;hb=e8964a486b2d0915617116eedf8b34670d443fbf;hp=4b83b52a610b005ae6a2330af0b9a327e07326a1;hpb=be33dbc967b4915cfdb0307ae1b7ae3cee651b8c;p=ghc-hetmet.git

diff --git a/ghc/compiler/basicTypes/UniqSupply.lhs b/ghc/compiler/basicTypes/UniqSupply.lhs
index 4b83b52..218df9e 100644
--- a/ghc/compiler/basicTypes/UniqSupply.lhs
+++ b/ghc/compiler/basicTypes/UniqSupply.lhs
@@ -1,5 +1,5 @@
 %
-% (c) The GRASP/AQUA Project, Glasgow University, 1992-1996
+% (c) The GRASP/AQUA Project, Glasgow University, 1992-1998
 %
 \section[UniqSupply]{The @UniqueSupply@ data type and a (monadic) supply thereof}
 
@@ -8,12 +8,14 @@ module UniqSupply (
 
 	UniqSupply,		-- Abstractly
 
-	getUnique, getUniques,	-- basic ops
+	uniqFromSupply, uniqsFromSupply,	-- basic ops
 
 	UniqSM,		-- type: unique supply monad
-	initUs, thenUs, returnUs, fixUs,
+	initUs, initUs_, thenUs, thenUs_, returnUs, fixUs, getUs, withUs,
+	getUniqueUs, getUniquesUs,
 	mapUs, mapAndUnzipUs, mapAndUnzip3Us,
 	thenMaybeUs, mapAccumLUs,
+	lazyThenUs, lazyMapUs,
 
 	mkSplitUniqSupply,
 	splitUniqSupply
@@ -22,8 +24,6 @@ module UniqSupply (
 #include "HsVersions.h"
 
 import Unique
-import Util
-
 import GlaExts
 
 #if __GLASGOW_HASKELL__ < 301
@@ -65,8 +65,8 @@ data UniqSupply
 mkSplitUniqSupply :: Char -> IO UniqSupply
 
 splitUniqSupply :: UniqSupply -> (UniqSupply, UniqSupply)
-getUnique :: UniqSupply -> Unique
-getUniques :: Int -> UniqSupply -> [Unique]
+uniqFromSupply  :: UniqSupply -> Unique
+uniqsFromSupply :: UniqSupply -> [Unique]	-- Infinite
 \end{code}
 
 \begin{code}
@@ -94,13 +94,8 @@ splitUniqSupply (MkSplitUniqSupply _ s1 s2) = (s1, s2)
 \end{code}
 
 \begin{code}
-getUnique (MkSplitUniqSupply (I# n) _ _) = mkUniqueGrimily n
-
-getUniques (I# i) supply = i `get_from` supply
-  where
-    get_from 0# _ = []
-    get_from n (MkSplitUniqSupply (I# u) _ s2)
-      = mkUniqueGrimily u : get_from (n -# 1#) s2
+uniqFromSupply  (MkSplitUniqSupply (I# n) _ _)  = mkUniqueGrimily n
+uniqsFromSupply (MkSplitUniqSupply (I# n) _ s2) = mkUniqueGrimily n : uniqsFromSupply s2
 \end{code}
 
 %************************************************************************
@@ -110,15 +105,17 @@ getUniques (I# i) supply = i `get_from` supply
 %************************************************************************
 
 \begin{code}
-type UniqSM result = UniqSupply -> result
-
--- the initUs function also returns the final UniqSupply
+type UniqSM result = UniqSupply -> (result, UniqSupply)
 
-initUs :: UniqSupply -> UniqSM a -> a
+-- the initUs function also returns the final UniqSupply; initUs_ drops it
+initUs :: UniqSupply -> UniqSM a -> (a,UniqSupply)
+initUs init_us m = case m init_us of { (r,us) -> (r,us) }
 
-initUs init_us m = m init_us
+initUs_ :: UniqSupply -> UniqSM a -> a
+initUs_ init_us m = case m init_us of { (r,us) -> r }
 
 {-# INLINE thenUs #-}
+{-# INLINE lazyThenUs #-}
 {-# INLINE returnUs #-}
 {-# INLINE splitUniqSupply #-}
 \end{code}
@@ -127,28 +124,54 @@ initUs init_us m = m init_us
 \begin{code}
 fixUs :: (a -> UniqSM a) -> UniqSM a
 fixUs m us
-  = r  where  r = m r us
+  = (r,us')  where  (r,us') = m r us
 
 thenUs :: UniqSM a -> (a -> UniqSM b) -> UniqSM b
-
 thenUs expr cont us
-  = case (splitUniqSupply us) of { (s1, s2) ->
-    case (expr s1)	      of { result ->
-    cont result s2 }}
-\end{code}
+  = case (expr us) of { (result, us') -> cont result us' }
+
+lazyThenUs :: UniqSM a -> (a -> UniqSM b) -> UniqSM b
+lazyThenUs expr cont us
+  = let (result, us') = expr us in cont result us'
+
+thenUs_ :: UniqSM a -> UniqSM b -> UniqSM b
+thenUs_ expr cont us
+  = case (expr us) of { (_, us') -> cont us' }
+
 
-\begin{code}
 returnUs :: a -> UniqSM a
-returnUs result us = result
+returnUs result us = (result, us)
 
-mapUs :: (a -> UniqSM b) -> [a] -> UniqSM [b]
+withUs :: (UniqSupply -> (a, UniqSupply)) -> UniqSM a
+withUs f us = f us	-- Ha ha!
+		
+getUs :: UniqSM UniqSupply
+getUs us = splitUniqSupply us
+
+getUniqueUs :: UniqSM Unique
+getUniqueUs us = case splitUniqSupply us of
+		   (us1,us2) -> (uniqFromSupply us1, us2)
+
+getUniquesUs :: UniqSM [Unique]
+getUniquesUs us = case splitUniqSupply us of
+		      (us1,us2) -> (uniqsFromSupply us1, us2)
+\end{code}
 
+\begin{code}
+mapUs :: (a -> UniqSM b) -> [a] -> UniqSM [b]
 mapUs f []     = returnUs []
 mapUs f (x:xs)
   = f x         `thenUs` \ r  ->
     mapUs f xs  `thenUs` \ rs ->
     returnUs (r:rs)
 
+lazyMapUs :: (a -> UniqSM b) -> [a] -> UniqSM [b]
+lazyMapUs f []     = returnUs []
+lazyMapUs f (x:xs)
+  = f x             `lazyThenUs` \ r  ->
+    lazyMapUs f xs  `lazyThenUs` \ rs ->
+    returnUs (r:rs)
+
 mapAndUnzipUs  :: (a -> UniqSM (b,c))   -> [a] -> UniqSM ([b],[c])
 mapAndUnzip3Us :: (a -> UniqSM (b,c,d)) -> [a] -> UniqSM ([b],[c],[d])