[project @ 1999-06-01 16:40:41 by simonmar]

[ghc-hetmet.git] / ghc / compiler / basicTypes / Demand.lhs

diff --git a/ghc/compiler/basicTypes/Demand.lhs b/ghc/compiler/basicTypes/Demand.lhs
index 0f25717..7a4dbfe 100644 (file)
--- a/ghc/compiler/basicTypes/Demand.lhs
+++ b/ghc/compiler/basicTypes/Demand.lhs
@@ -8,7 +8,7 @@ module Demand(
        Demand(..),
 
        wwLazy, wwStrict, wwUnpackData, wwUnpackNew, wwPrim, wwEnum, 
-       isStrict, isLazy, 
+       isStrict, isLazy, isPrim,
 
        pprDemands
      ) where
@@ -78,10 +78,12 @@ isStrict (WwUnpack NewType _ ds) = isStrict (head ds)
 isStrict (WwUnpack other _ _)    = True
 isStrict WwStrict = True
 isStrict WwEnum          = True
-isStrict WwPrim          = False       -- NB: we treat only lifted types as strict.
-                               -- Why is this important?  Mostly it doesn't matter
-                               -- but it saves a test for lifted-ness in SimplUtils.etaCoreExpr
+isStrict WwPrim          = True
 isStrict _       = False
+
+isPrim :: Demand -> Bool
+isPrim WwPrim = True
+isPrim other  = False
 \end{code}
 
 \begin{code}
@@ -97,7 +99,42 @@ isLazy _           = False   -- (as they imply a worker)
 %*                                                                     *
 %************************************************************************
 
+
+\begin{code}
+pprDemands demands bot = hcat (map pprDemand demands) <> pp_bot
+                      where
+                        pp_bot | bot       = ptext SLIT("B")
+                               | otherwise = empty
+
+
+pprDemand (WwLazy False)        = char 'L'
+pprDemand (WwLazy True)         = char 'A'
+pprDemand WwStrict              = char 'S'
+pprDemand WwPrim                = char 'P'
+pprDemand WwEnum                = char 'E'
+pprDemand (WwUnpack nd wu args)  = char ch <> parens (hcat (map pprDemand args))
+                                     where
+                                       ch = case nd of
+                                               DataType | wu        -> 'U'
+                                                        | otherwise -> 'u'
+                                               NewType  | wu        -> 'N'
+                                                        | otherwise -> 'n'
+
+instance Outputable Demand where
+    ppr (WwLazy False) = empty
+    ppr other_demand   = ptext SLIT("__D") <+> pprDemand other_demand
+
+instance Show Demand where
+    showsPrec p d = showsPrecSDoc p (ppr d)
+\end{code}
+
+
 \begin{code}
+{-     ------------------- OMITTED NOW -------------------------------
+       -- Reading demands is done in Lex.lhs
+       -- Also note that the (old) code here doesn't take proper
+       -- account of the 'B' suffix for bottoming functions
+
 #ifdef REALLY_HASKELL_1_3
 
 instance Read Demand where
@@ -113,6 +150,8 @@ instance Text Demand where
     showsPrec p d = showsPrecSDoc p (ppr d)
 #endif
 
+readDemands :: String -> 
+
 read_em acc ('L' : xs) = read_em (WwLazy   False : acc) xs
 read_em acc ('A' : xs) = read_em (WwLazy   True  : acc) xs
 read_em acc ('S' : xs) = read_em (WwStrict : acc) xs
@@ -128,25 +167,8 @@ read_em acc rest   = [(reverse acc, rest)]
 do_unpack new_or_data wrapper_unpacks acc xs
          = case (read_em [] xs) of
              [(stuff, rest)] -> read_em (WwUnpack new_or_data wrapper_unpacks stuff : acc) rest
-             _ -> pprPanic "Demand.do_unpack:" (ppr acc <+> text ("::"++xs))
-
+             _ -> pprPanic "Demand.do_unpack:" (ppr acc <+> dcolon <> text xs)
 
-pprDemands demands = hcat (map pprDemand demands)
-
-pprDemand (WwLazy False)        = char 'L'
-pprDemand (WwLazy True)         = char 'A'
-pprDemand WwStrict              = char 'S'
-pprDemand WwPrim                = char 'P'
-pprDemand WwEnum                = char 'E'
-pprDemand (WwUnpack nd wu args)  = char ch <> parens (pprDemands args)
-                                     where
-                                       ch = case nd of
-                                               DataType | wu        -> 'U'
-                                                        | otherwise -> 'u'
-                                               NewType  | wu        -> 'N'
-                                                        | otherwise -> 'n'
-
-instance Outputable Demand where
-    ppr (WwLazy False) = empty
-    ppr other_demand   = ptext SLIT("__D") <+> pprDemand other_demand
+-------------------- END OF OMISSION ------------------------------  -}
 \end{code}
+