[project @ 1998-04-07 16:40:08 by simonpj]

[ghc-hetmet.git] / ghc / compiler / types / TyVar.lhs

diff --git a/ghc/compiler/types/TyVar.lhs b/ghc/compiler/types/TyVar.lhs
index fd59f96..e0d4178 100644 (file)
--- a/ghc/compiler/types/TyVar.lhs
+++ b/ghc/compiler/types/TyVar.lhs
@@ -1,47 +1,45 @@
 \begin{code}
-#include "HsVersions.h"
-
 module TyVar (
-       GenTyVar(..), SYN_IE(TyVar),
-       mkTyVar, mkSysTyVar,
-       tyVarKind,              -- TyVar -> Kind
-       cloneTyVar,
+       GenTyVar(..), TyVar, 
+
+       mkTyVar, mkSysTyVar, 
+       tyVarKind,              -- TyVar -> Kind
+        tyVarFlexi,             -- GenTyVar flexi -> flexi
+        setTyVarFlexi,
+       cloneTyVar, nameTyVar,
 
        openAlphaTyVar,
        alphaTyVars, alphaTyVar, betaTyVar, gammaTyVar, deltaTyVar,
 
        -- We also export "environments" keyed off of
        -- TyVars and "sets" containing TyVars:
-       SYN_IE(TyVarEnv),
-       nullTyVarEnv, mkTyVarEnv, addOneToTyVarEnv,
-       growTyVarEnvList, isNullTyVarEnv, lookupTyVarEnv, delFromTyVarEnv,
+       TyVarEnv,
+       emptyTyVarEnv, mkTyVarEnv, zipTyVarEnv, addToTyVarEnv, plusTyVarEnv,
+       growTyVarEnvList, isEmptyTyVarEnv, lookupTyVarEnv, delFromTyVarEnv,
 
-       SYN_IE(GenTyVarSet), SYN_IE(TyVarSet),
-       emptyTyVarSet, unitTyVarSet, unionTyVarSets,
+       GenTyVarSet, TyVarSet,
+       emptyTyVarSet, unitTyVarSet, unionTyVarSets, addOneToTyVarSet,
        unionManyTyVarSets, intersectTyVarSets, mkTyVarSet,
        tyVarSetToList, elementOfTyVarSet, minusTyVarSet,
-       isEmptyTyVarSet
+       isEmptyTyVarSet, delOneFromTyVarSet
   ) where
 
-CHK_Ubiq()     -- debugging consistency check
---IMPORT_DELOOPER(IdLoop)      -- for paranoia checking
+#include "HsVersions.h"
 
 -- friends
-import Usage           ( GenUsage, SYN_IE(Usage), usageOmega )
 import Kind            ( Kind, mkBoxedTypeKind, mkTypeKind )
 
 -- others
 import UniqSet         -- nearly all of it
-import UniqFM          ( emptyUFM, listToUFM, addToUFM, lookupUFM,
-                         plusUFM, sizeUFM, delFromUFM, UniqFM
+import UniqFM          ( emptyUFM, listToUFM, addToUFM, lookupUFM, delFromUFM,
+                         plusUFM, sizeUFM, delFromUFM, isNullUFM, UniqFM
                        )
-import Name            ( mkSysLocalName, changeUnique, Name )
-import Pretty          ( SYN_IE(Pretty), PrettyRep, ppBeside, ppPStr )
-import PprStyle                ( PprStyle )
---import Outputable    ( Outputable(..), NamedThing(..), ExportFlag(..) )
+import BasicTypes      ( Unused, unused )
+import Name            ( mkSysLocalName, mkLocalName, Name, NamedThing(..), OccName )
 import SrcLoc          ( noSrcLoc, SrcLoc )
-import Unique          ( showUnique, mkAlphaTyVarUnique, Unique )
-import Util            ( panic, Ord3(..) )
+import Unique          ( initTyVarUnique, incrUnique, Unique, Uniquable(..) )
+import Util            ( zipEqual )
+import Outputable
 \end{code}
 
 \begin{code}
@@ -53,7 +51,13 @@ data GenTyVar flexi_slot
        flexi_slot              -- Extra slot used during type and usage
                                -- inference, and to contain usages.
 
-type TyVar = GenTyVar Usage    -- Usage slot makes sense only if Kind = Type
+type TyVar   = GenTyVar Unused
+
+tyVarFlexi :: GenTyVar flexi -> flexi
+tyVarFlexi (TyVar _ _ _ flex) = flex
+
+setTyVarFlexi :: GenTyVar flexi1 -> flexi2 -> GenTyVar flexi2
+setTyVarFlexi (TyVar u k n _) flex = TyVar u k n flex
 \end{code}
 
 
@@ -64,19 +68,24 @@ mkTyVar :: Name -> Kind -> TyVar
 mkTyVar name kind = TyVar  (uniqueOf name)
                           kind
                           (Just name)
-                          usageOmega
+                          unused
 
 mkSysTyVar :: Unique -> Kind -> TyVar
 mkSysTyVar uniq kind = TyVar uniq
                             kind
                             Nothing
-                            usageOmega
+                            unused
 
 tyVarKind :: GenTyVar flexi -> Kind
 tyVarKind (TyVar _ kind _ _) = kind
 
 cloneTyVar :: GenTyVar flexi -> Unique -> GenTyVar flexi
-cloneTyVar (TyVar _ k n x) u = TyVar u k n x
+cloneTyVar (TyVar _ k n x) u = TyVar u k Nothing x
+       -- Zaps its name
+
+nameTyVar :: GenTyVar flexi -> OccName -> GenTyVar flexi
+       -- Give the TyVar a print-name
+nameTyVar (TyVar u k n x) occ = TyVar u k (Just (mkLocalName u occ noSrcLoc)) x
 \end{code}
 
 
@@ -86,10 +95,10 @@ Fixed collection of type variables
        -- openAlphaTyVar is prepared to be instantiated
        -- to a boxed or unboxed type variable.  It's used for the 
        -- result type for "error", so that we can have (error Int# "Help")
-openAlphaTyVar = TyVar (mkAlphaTyVarUnique 1) mkTypeKind Nothing usageOmega
+openAlphaTyVar = TyVar initTyVarUnique mkTypeKind Nothing unused
 
-alphaTyVars = [ TyVar u mkBoxedTypeKind Nothing usageOmega
-             | u <- map mkAlphaTyVarUnique [2..] ]
+alphaTyVars = [ TyVar u mkBoxedTypeKind Nothing unused
+             | u <- iterate incrUnique initTyVarUnique]
 
 (alphaTyVar:betaTyVar:gammaTyVar:deltaTyVar:_) = alphaTyVars
 
@@ -101,22 +110,26 @@ Environments
 \begin{code}
 type TyVarEnv elt = UniqFM elt
 
-nullTyVarEnv    :: TyVarEnv a
+emptyTyVarEnv   :: TyVarEnv a
 mkTyVarEnv      :: [(GenTyVar flexi, a)] -> TyVarEnv a
-addOneToTyVarEnv :: TyVarEnv a -> GenTyVar flexi -> a -> TyVarEnv a
+zipTyVarEnv     :: [GenTyVar flexi] -> [a] -> TyVarEnv a
+addToTyVarEnv    :: TyVarEnv a -> GenTyVar flexi -> a -> TyVarEnv a
 growTyVarEnvList :: TyVarEnv a -> [(GenTyVar flexi, a)] -> TyVarEnv a
-isNullTyVarEnv  :: TyVarEnv a -> Bool
+isEmptyTyVarEnv         :: TyVarEnv a -> Bool
 lookupTyVarEnv  :: TyVarEnv a -> GenTyVar flexi -> Maybe a
 delFromTyVarEnv         :: TyVarEnv a -> GenTyVar flexi -> TyVarEnv a
+plusTyVarEnv     :: TyVarEnv a -> TyVarEnv a -> TyVarEnv a
 
-nullTyVarEnv    = emptyUFM
+emptyTyVarEnv   = emptyUFM
 mkTyVarEnv      = listToUFM
-addOneToTyVarEnv = addToUFM
+addToTyVarEnv    = addToUFM
 lookupTyVarEnv   = lookupUFM
 delFromTyVarEnv  = delFromUFM
+plusTyVarEnv     = plusUFM
+isEmptyTyVarEnv  = isNullUFM
 
+zipTyVarEnv tyvars tys     = listToUFM (zipEqual "zipTyVarEnv" tyvars tys)
 growTyVarEnvList env pairs = plusUFM env (listToUFM pairs)
-isNullTyVarEnv   env      = sizeUFM env == 0
 \end{code}
 
 Sets
@@ -135,9 +148,13 @@ elementOfTyVarSet :: GenTyVar flexi -> GenTyVarSet flexi -> Bool
 minusTyVarSet    :: GenTyVarSet flexi -> GenTyVarSet flexi -> GenTyVarSet flexi
 isEmptyTyVarSet   :: GenTyVarSet flexi -> Bool
 mkTyVarSet       :: [GenTyVar flexi] -> GenTyVarSet flexi
+addOneToTyVarSet  :: GenTyVarSet flexi -> GenTyVar flexi -> GenTyVarSet flexi
+delOneFromTyVarSet :: GenTyVarSet flexi -> GenTyVar flexi -> GenTyVarSet flexi
 
 emptyTyVarSet            = emptyUniqSet
-unitTyVarSet = unitUniqSet
+unitTyVarSet      = unitUniqSet
+addOneToTyVarSet  = addOneToUniqSet
+delOneFromTyVarSet = delOneFromUniqSet
 intersectTyVarSets= intersectUniqSets
 unionTyVarSets           = unionUniqSets
 unionManyTyVarSets= unionManyUniqSets
@@ -154,8 +171,8 @@ Instance delarations
 instance Eq (GenTyVar a) where
     (TyVar u1 _ _ _) == (TyVar u2 _ _ _) = u1 == u2
 
-instance Ord3 (GenTyVar a) where
-    cmp (TyVar u1 _ _ _) (TyVar u2 _ _ _) = u1 `cmp` u2
+instance Ord (GenTyVar a) where
+    compare (TyVar u1 _ _ _) (TyVar u2 _ _ _) = u1 `compare` u2
 
 instance Uniquable (GenTyVar a) where
     uniqueOf (TyVar u _ _ _) = u