5 import List (elemIndex)
8 = Module AnMname [Tdef] [Vdefg]
11 = Data (Qual Tcon) [Tbind] [Cdef]
12 | Newtype (Qual Tcon) [Tbind] Axiom (Maybe Ty)
15 = Constr (Qual Dcon) [Tbind] [Ty]
18 type Axiom = (Qual Tcon, [Tbind], (Ty,Ty))
24 newtype Vdef = Vdef (Qual Var,Ty,Exp)
34 | Case Exp Vbind Ty [Alt] {- non-empty list -}
44 = Acon (Qual Dcon) [Tbind] [Vbind] Exp
49 type Tbind = (Tvar,Kind)
56 -- Wired-in coercions:
57 -- These are primitive tycons in GHC, but in ext-core,
58 -- we make them explicit, to make the typechecker
59 -- somewhat more clear.
62 | UnsafeCoercion Ty Ty
74 -- A CoercionKind isn't really a Kind at all, but rather,
75 -- corresponds to an arbitrary user-declared axiom.
76 -- A tycon whose CoercionKind is (DefinedCoercion <tbs> (from, to))
77 -- represents a tycon with arity (length tbs), whose kind is
78 -- (from :=: to) (modulo substituting type arguments.
79 -- It's not a Kind because a coercion must always be fully applied:
80 -- whenever we see a tycon that has such a CoercionKind, it must
81 -- be fully applied if it's to be assigned an actual Kind.
82 -- So, a CoercionKind *only* appears in the environment (mapping
83 -- newtype axioms onto CoercionKinds).
86 DefinedCoercion [Tbind] (Ty,Ty)
88 -- The type constructor environment maps names that are
89 -- either type constructors or coercion names onto either
90 -- kinds or coercion kinds.
91 data KindOrCoercion = Kind Kind | Coercion CoercionKind
93 data Lit = Literal CoreLit Ty
94 deriving Eq -- with nearlyEqualTy
96 data CoreLit = Lint Integer
102 -- Right now we represent module names as triples:
103 -- (package name, hierarchical names, leaf name)
104 -- An alternative to this would be to flatten the
105 -- module namespace, either when printing out
106 -- Core or (probably preferably) in a
108 -- We represent the empty module name (as in an unqualified name)
111 type Mname = Maybe AnMname
112 newtype AnMname = M (Pname, [Id], Id)
120 type Qual t = (Mname,t)
122 qual :: AnMname -> t -> Qual t
123 qual mn t = (Just mn, t)
125 unqual :: t -> Qual t
130 eqKind :: Kind -> Kind -> Bool
131 eqKind Klifted Klifted = True
132 eqKind Kunlifted Kunlifted = True
133 eqKind Kopen Kopen = True
134 eqKind (Karrow k1 k2) (Karrow l1 l2) = k1 `eqKind` l1
136 eqKind (Keq t1 t2) (Keq u1 u2) = t1 == u1
140 splitTyConApp_maybe :: Ty -> Maybe (Qual Tcon,[Ty])
141 splitTyConApp_maybe (Tvar _) = Nothing
142 splitTyConApp_maybe (Tcon t) = Just (t,[])
143 splitTyConApp_maybe (Tapp rator rand) =
144 case (splitTyConApp_maybe rator) of
145 Just (r,rs) -> Just (r,rs++[rand])
146 Nothing -> case rator of
147 Tcon tc -> Just (tc,[rand])
149 splitTyConApp_maybe t@(Tforall _ _) = Nothing
151 {- Doesn't expand out fully applied newtype synonyms
152 (for which an environment is needed). -}
153 nearlyEqualTy t1 t2 = eqTy [] [] t1 t2
154 where eqTy e1 e2 (Tvar v1) (Tvar v2) =
155 case (elemIndex v1 e1,elemIndex v2 e2) of
156 (Just i1, Just i2) -> i1 == i2
157 (Nothing, Nothing) -> v1 == v2
159 eqTy e1 e2 (Tcon c1) (Tcon c2) = c1 == c2
160 eqTy e1 e2 (Tapp t1a t1b) (Tapp t2a t2b) =
161 eqTy e1 e2 t1a t2a && eqTy e1 e2 t1b t2b
162 eqTy e1 e2 (Tforall (tv1,tk1) t1) (Tforall (tv2,tk2) t2) =
163 tk1 `eqKind` tk2 && eqTy (tv1:e1) (tv2:e2) t1 t2
165 instance Eq Ty where (==) = nearlyEqualTy
168 subKindOf :: Kind -> Kind -> Bool
169 _ `subKindOf` Kopen = True
170 (Karrow a1 r1) `subKindOf` (Karrow a2 r2) =
171 a2 `subKindOf` a1 && (r1 `subKindOf` r2)
172 k1 `subKindOf` k2 = k1 `eqKind` k2 -- doesn't worry about higher kinds
174 baseKind :: Kind -> Bool
175 baseKind (Karrow _ _ ) = False
178 isPrimVar (Just mn,_) = mn == primMname
181 primMname = mkPrimMname "Prim"
182 errMname = mkBaseMname "Err"
183 mkBaseMname,mkPrimMname :: Id -> AnMname
184 mkBaseMname mn = M (basePkg, ghcPrefix, mn)
185 mkPrimMname mn = M (primPkg, ghcPrefix, mn)
188 primPkg = zEncodeString "ghc-prim"
191 baseMname = mkBaseMname "Base"
192 boolMname = mkPrimMname "Bool"
193 mainVar = qual mainMname "main"
194 mainMname = M (mainPkg, mainPrefix, "Main")
195 wrapperMainMname = Just $ M (mainPkg, mainPrefix, "ZCMain")
198 tcArrow = (Just primMname, "ZLzmzgZR")
200 tArrow :: Ty -> Ty -> Ty
201 tArrow t1 t2 = Tapp (Tapp (Tcon tcArrow) t1) t2
205 ktArrow = Karrow Kopen (Karrow Kopen Klifted)
212 tcUtuple :: Int -> Qual Tcon
213 tcUtuple n = (Just primMname,"Z"++ (show n) ++ "H")
215 ktUtuple :: Int -> Kind
216 ktUtuple n = foldr Karrow Kunlifted (replicate n Kopen)
218 tUtuple :: [Ty] -> Ty
219 tUtuple ts = foldl Tapp (Tcon (tcUtuple (length ts))) ts
221 isUtupleTy :: Ty -> Bool
222 isUtupleTy (Tapp t _) = isUtupleTy t
223 isUtupleTy (Tcon tc) = tc `elem` [tcUtuple n | n <- [1..maxUtuple]]
226 dcUtuple :: Int -> Qual Dcon
227 -- TODO: Seems like Z2H etc. appears in ext-core files,
228 -- not $wZ2H etc. Is this right?
229 dcUtuple n = (Just primMname,"Z" ++ (show n) ++ "H")
231 isUtupleDc :: Qual Dcon -> Bool
232 isUtupleDc dc = dc `elem` [dcUtuple n | n <- [1..maxUtuple]]
234 dcUtupleTy :: Int -> Ty
236 foldr ( \tv t -> Tforall (tv,Kopen) t)
237 (foldr ( \tv t -> tArrow (Tvar tv) t)
238 (tUtuple (map Tvar tvs)) tvs)
240 where tvs = map ( \i -> ("a" ++ (show i))) [1..n]
242 utuple :: [Ty] -> [Exp] -> Exp
243 utuple ts es = foldl App (foldl Appt (Dcon (dcUtuple (length es))) ts) es