X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=ghc%2Fcompiler%2Ftypes%2FClass.lhs;h=3385adc2b31336c139763b321a4e486092936d74;hb=c883f6969ad957637649f3af1a2b6977555bdd32;hp=5347b01b0562c7b97b0d5d20e6d0a300a8f0a129;hpb=5a6336b843105764711c4524626d09b59bccff20;p=ghc-hetmet.git

diff --git a/ghc/compiler/types/Class.lhs b/ghc/compiler/types/Class.lhs
index 5347b01..3385adc 100644
--- a/ghc/compiler/types/Class.lhs
+++ b/ghc/compiler/types/Class.lhs
@@ -1,52 +1,28 @@
 %
-% (c) The GRASP/AQUA Project, Glasgow University, 1992-1996
+% (c) The GRASP/AQUA Project, Glasgow University, 1992-1998
 %
 \section[Class]{The @Class@ datatype}
 
 \begin{code}
-#include "HsVersions.h"
-
 module Class (
-	GenClass(..), SYN_IE(Class),
+	Class, ClassOpItem, FunDep,
+	DefMeth (..),
 
-	mkClass,
-	classKey, classSelIds, classDictArgTys,
-	classSuperDictSelId, classDefaultMethodId,
-	classBigSig, classInstEnv,
-	isSuperClassOf,
-	classOpTagByOccName,
-
-	SYN_IE(ClassInstEnv)
+	mkClass, classTyVars, classArity,
+	classKey, className, classSelIds, classTyCon,
+	classBigSig, classExtraBigSig, classTvsFds, classSCTheta
     ) where
 
-CHK_Ubiq() -- debugging consistency check
-
-#if defined(__GLASGOW_HASKELL__) && __GLASGOW_HASKELL__ <= 201
-IMPORT_DELOOPER(TyLoop)
-IMPORT_DELOOPER(IdLoop)
-#else
-import {-# SOURCE #-} Id	( Id, idType, idName )
-import {-# SOURCE #-} Type
-import {-# SOURCE #-} TysWiredIn
-import {-# SOURCE #-} TysPrim
-#endif
-
-#if __GLASGOW_HASKELL__ >= 202
-import Name
-#endif
-
-import TyCon		( TyCon )
-import TyVar		( SYN_IE(TyVar), GenTyVar )
-import Usage		( GenUsage, SYN_IE(Usage), SYN_IE(UVar) )
-
-import MatchEnv		( MatchEnv )
-import Maybes		( assocMaybe )
-import Name		( changeUnique, Name, OccName, occNameString )
-import Unique		-- Keys for built-in classes
-import Pretty		( Doc, hsep, ptext )
-import SrcLoc		( SrcLoc )
+#include "HsVersions.h"
+
+import {-# SOURCE #-} TyCon	( TyCon )
+import {-# SOURCE #-} TypeRep	( PredType )
+
+import Var		( Id, TyVar )
+import Name		( NamedThing(..), Name )
+import BasicTypes	( Arity )
+import Unique		( Unique, Uniquable(..) )
 import Outputable
-import Util
 \end{code}
 
 %************************************************************************
@@ -57,71 +33,58 @@ import Util
 
 A @Class@ corresponds to a Greek kappa in the static semantics:
 
-The parameterisation wrt tyvar and uvar is only necessary to
-get appropriately general instances of Ord3 for GenType.
-
 \begin{code}
-data GenClass tyvar uvar
-  = Class
-	Unique		-- Key for fast comparison
-	Name
-
-	tyvar	  	-- The class type variable
-
-	[GenClass tyvar uvar] 	-- Immediate superclasses, and the
-	[Id]			-- corresponding selector functions to
-				-- extract them from a dictionary of this
-			  	-- class
-
-	[Id]			 	  --	 * selector functions
-	[Maybe Id]			  --	 * default methods
-			  -- They are all ordered by tag.  The
-			  -- selector ids are less innocent than they
-			  -- look, because their IdInfos contains
-			  -- suitable specialisation information.  In
-			  -- particular, constant methods are
-			  -- instances of selectors at suitably simple
-			  -- types.
-
-	ClassInstEnv	  -- Gives details of all the instances of this class
-
-	[(GenClass tyvar uvar, [GenClass tyvar uvar])]
-			  -- Indirect superclasses;
-			  --   (k,[k1,...,kn]) means that
-			  --   k is an immediate superclass of k1
-			  --   k1 is an immediate superclass of k2
-			  --   ... and kn is an immediate superclass
-			  -- of this class.  (This is all redundant
-			  -- information, since it can be derived from
-			  -- the superclass information above.)
-
-type Class        = GenClass TyVar UVar
-
-type ClassInstEnv = MatchEnv Type Id		-- The Ids are dfuns
+data Class
+  = Class {
+	classKey  :: Unique,			-- Key for fast comparison
+	className :: Name,
+	
+	classTyVars  :: [TyVar],		-- The class type variables
+	classFunDeps :: [FunDep TyVar],		-- The functional dependencies
+
+	classSCTheta :: [PredType],		-- Immediate superclasses, and the
+	classSCSels  :: [Id],			-- corresponding selector functions to
+						-- extract them from a dictionary of this
+						-- class
+
+	classOpStuff :: [ClassOpItem],		-- Ordered by tag
+
+	classTyCon :: TyCon		-- The data type constructor for dictionaries
+  }					-- of this class
+
+type FunDep a	  = ([a],[a])	--  e.g. class C a b c |  a b -> c, a c -> b  where ...
+				--  Here fun-deps are [([a,b],[c]), ([a,c],[b])]
+
+type ClassOpItem = (Id, DefMeth)
+	-- Selector function; contains unfolding
+	-- Default-method info
+
+data DefMeth = NoDefMeth 		-- No default method
+	     | DefMeth  		-- A polymorphic default method
+	     | GenDefMeth 		-- A generic default method
+             deriving Eq  
 \end{code}
 
 The @mkClass@ function fills in the indirect superclasses.
 
 \begin{code}
-mkClass :: Unique -> Name -> TyVar
-	-> [Class] -> [Id]
-	-> [Id] -> [Maybe Id]
-	-> ClassInstEnv
+mkClass :: Name -> [TyVar]
+	-> [([TyVar], [TyVar])]
+	-> [PredType] -> [Id]
+	-> [ClassOpItem]
+	-> TyCon
 	-> Class
 
-mkClass uniq full_name tyvar super_classes superdict_sels
-	dict_sels defms class_insts
-  = Class uniq (changeUnique full_name uniq) tyvar
-		super_classes superdict_sels
-		dict_sels defms
-		class_insts
-		trans_clos
-  where
-    trans_clos :: [(Class,[Class])]
-    trans_clos = transitiveClosure succ (==) [ (clas, []) | clas <- super_classes ]
-
-    succ (clas@(Class _ _ _ super_classes _ _ _ _ _), links)
-      = [(super, (clas:links)) | super <- super_classes]
+mkClass name tyvars fds super_classes superdict_sels
+	op_stuff tycon
+  = Class {	classKey = getUnique name, 
+		className = name,
+		classTyVars = tyvars,
+		classFunDeps = fds,
+		classSCTheta = super_classes,
+		classSCSels = superdict_sels,
+		classOpStuff = op_stuff,
+		classTyCon = tycon }
 \end{code}
 
 %************************************************************************
@@ -133,47 +96,25 @@ mkClass uniq full_name tyvar super_classes superdict_sels
 The rest of these functions are just simple selectors.
 
 \begin{code}
-classKey (Class key _ _ _ _ _ _ _ _) = key
-classSelIds (Class _ _ _ _ _ sels _ _ _) = sels
-
-classDefaultMethodId (Class _ _ _ _ _ _ defm_ids _ _) idx
-  = defm_ids !! idx
-
-classSuperDictSelId (Class _ _ _ scs scsel_ids _ _ _ _) super_clas
-  = assoc "classSuperDictSelId" (scs `zip` scsel_ids) super_clas
-
-classBigSig (Class _ _ tyvar super_classes sdsels sels defms _ _)
-  = (tyvar, super_classes, sdsels, sels, defms)
-
-classInstEnv (Class _ _ _ _ _ _ _ inst_env _) = inst_env
-
-classDictArgTys :: Class -> Type -> [Type]	-- Types of components of the dictionary (C ty)
-classDictArgTys (Class _ _ _ _ sc_sel_ids meth_sel_ids _ _ _) ty
-  = map mk_arg_ty (sc_sel_ids ++ meth_sel_ids)
-  where
-    mk_arg_ty id = case splitRhoTy (applyTy (idType id) ty) of
-			(sel_theta, meth_ty) -> ASSERT( length sel_theta == 1 )
-		   				meth_ty
-
-classOpTagByOccName clas occ
-  = go (classSelIds clas) 1
-  where
-    go (sel_id : sel_ids) tag 
-	    | getOccName (idName sel_id) == occ = tag
-	    | otherwise		                = go sel_ids (tag+1)
-    go [] _ = pprPanic "classOpTagByOccName"
-		(hsep [ppr PprDebug (getName clas), ppr PprDebug occ])
+classArity :: Class -> Arity
+classArity clas = length (classTyVars clas)
+	-- Could memoise this
+
+classSelIds (Class {classSCSels = sc_sels, classOpStuff = op_stuff})
+  = sc_sels ++ [op_sel | (op_sel, _) <- op_stuff]
+
+classTvsFds c
+  = (classTyVars c, classFunDeps c)
+
+classBigSig (Class {classTyVars = tyvars, classSCTheta = sc_theta, 
+	 	    classSCSels = sc_sels, classOpStuff = op_stuff})
+  = (tyvars, sc_theta, sc_sels, op_stuff)
+classExtraBigSig (Class {classTyVars = tyvars, classFunDeps = fundeps,
+			 classSCTheta = sc_theta, classSCSels = sc_sels,
+			 classOpStuff = op_stuff})
+  = (tyvars, fundeps, sc_theta, sc_sels, op_stuff)
 \end{code}
 
-@a `isSuperClassOf` b@ returns @Nothing@ if @a@ is not a superclass of
-@b@, but if it is, it returns $@Just@~[k_1,\ldots,k_n]$, where the
-$k_1,\ldots,k_n$ are exactly as described in the definition of the
-@GenClass@ constructor above.
-
-\begin{code}
-isSuperClassOf :: Class -> Class -> Maybe [Class]
-clas `isSuperClassOf` (Class _ _ _ _ _ _ _ _ links) = assocMaybe links clas
-\end{code}
 
 %************************************************************************
 %*									*
@@ -184,27 +125,35 @@ clas `isSuperClassOf` (Class _ _ _ _ _ _ _ _ links) = assocMaybe links clas
 We compare @Classes@ by their keys (which include @Uniques@).
 
 \begin{code}
-instance Ord3 (GenClass tyvar uvar) where
-  cmp (Class k1 _ _ _ _ _ _ _ _) (Class k2 _ _ _ _ _ _ _ _)  = cmp k1 k2
-
-instance Eq (GenClass tyvar uvar) where
-    (Class k1 _ _ _ _ _ _ _ _) == (Class k2 _ _ _ _ _ _ _ _) = k1 == k2
-    (Class k1 _ _ _ _ _ _ _ _) /= (Class k2 _ _ _ _ _ _ _ _) = k1 /= k2
-
-instance Ord (GenClass tyvar uvar) where
-    (Class k1 _ _ _ _ _ _ _ _) <= (Class k2 _ _ _ _ _ _ _ _) = k1 <= k2
-    (Class k1 _ _ _ _ _ _ _ _) <  (Class k2 _ _ _ _ _ _ _ _) = k1 <  k2
-    (Class k1 _ _ _ _ _ _ _ _) >= (Class k2 _ _ _ _ _ _ _ _) = k1 >= k2
-    (Class k1 _ _ _ _ _ _ _ _) >  (Class k2 _ _ _ _ _ _ _ _) = k1 >  k2
-    _tagCmp a b = case cmp a b of { LT_ -> _LT; EQ_ -> _EQ; GT__ -> _GT }
+instance Eq Class where
+    c1 == c2 = classKey c1 == classKey c2
+    c1 /= c2 = classKey c1 /= classKey c2
+
+instance Ord Class where
+    c1 <= c2 = classKey c1 <= classKey c2
+    c1 <  c2 = classKey c1 <  classKey c2
+    c1 >= c2 = classKey c1 >= classKey c2
+    c1 >  c2 = classKey c1 >  classKey c2
+    compare c1 c2 = classKey c1 `compare` classKey c2
 \end{code}
 
 \begin{code}
-instance Uniquable (GenClass tyvar uvar) where
-    uniqueOf (Class u _ _ _ _ _ _ _ _) = u
+instance Uniquable Class where
+    getUnique c = classKey c
+
+instance NamedThing Class where
+    getName clas = className clas
+
+instance Outputable Class where
+    ppr c = ppr (getName c)
+
+instance Show Class where
+    showsPrec p c = showsPrecSDoc p (ppr c)
 
-instance NamedThing (GenClass tyvar uvar) where
-    getName (Class _ n _ _ _ _ _ _ _) = n
+instance Outputable DefMeth where
+    ppr DefMeth     =  text "{- has default method -}"
+    ppr GenDefMeth  =  text "{- has generic method -}"
+    ppr NoDefMeth   =  empty   -- No default method
 \end{code}