1 module Language.Core.CoreUtils where
3 import Language.Core.Core
4 import Language.Core.Utils
5 import Language.Core.Printer()
13 splitDataConApp_maybe :: Exp -> Maybe (Qual Dcon, [Ty], [Exp])
14 splitDataConApp_maybe (Dcon d) = Just (d, [], [])
15 splitDataConApp_maybe (Appt rator t) =
16 case splitDataConApp_maybe rator of
17 Just (r, ts, rs) -> Just (r, ts ++ [t], rs)
19 splitDataConApp_maybe (App rator rand) =
20 case splitDataConApp_maybe rator of
21 Just (r, ts, rs) -> Just (r, ts, rs++[rand])
23 splitDataConApp_maybe _ = Nothing
25 splitApp :: Exp -> (Exp, [Exp])
26 splitApp (Appt rator _) = splitApp rator
27 splitApp (App rator rand) =
28 case splitApp rator of
29 (r, rs) -> (r, rs++[rand])
32 splitAppIgnoreCasts :: Exp -> (Exp, [Exp])
33 splitAppIgnoreCasts (Appt rator _) = splitApp rator
34 splitAppIgnoreCasts (App (Cast rator _) rand) = splitApp (App rator rand)
35 splitAppIgnoreCasts (App rator rand) =
36 case splitApp rator of
37 (r, rs) -> (r, rs++[rand])
38 splitAppIgnoreCasts e = (e, [])
40 splitFunTy_maybe :: Ty -> Maybe ([Ty], Ty)
41 splitFunTy_maybe (Tforall _ t) = splitFunTy_maybe t
43 case splitFunTy2_maybe t of
44 Just (rator, rand) -> case splitFunTy_maybe rand of
45 Just (r,s) -> Just (rator:r, s)
46 Nothing -> Just ([rator], rand)
49 splitFunTy2_maybe :: Ty -> Maybe (Ty,Ty)
50 splitFunTy2_maybe (Tapp (Tapp (Tcon c) t) u) | c == tcArrow = Just (t, u)
51 splitFunTy2_maybe _ = Nothing
53 vdefNamesQ :: [Vdef] -> [Qual Var]
54 vdefNamesQ = map (\ (Vdef (v,_,_)) -> v)
56 vdefNames :: [Vdef] -> [Var]
57 vdefNames = snd . unzip . vdefNamesQ
59 vdefTys :: [Vdef] -> [Ty]
60 vdefTys = map (\ (Vdef (_,t,_)) -> t)
62 vdefgNames :: Vdefg -> [Var]
63 vdefgNames = snd . unzip . vdefgNamesQ
65 vdefgNamesQ :: Vdefg -> [Qual Var]
66 vdefgNamesQ (Rec vds) = map (\ (Vdef (v,_,_)) -> v) vds
67 vdefgNamesQ (Nonrec (Vdef (v,_,_))) = [v]
69 vdefgTys :: Vdefg -> [Ty]
70 vdefgTys (Rec vds) = map (\ (Vdef (_,t,_)) -> t) vds
71 vdefgTys (Nonrec (Vdef (_,t,_))) = [t]
72 vdefgBodies :: Vdefg -> [Exp]
73 vdefgBodies (Rec vds) = map (\ (Vdef (_,_,e)) -> e) vds
74 vdefgBodies (Nonrec (Vdef (_,_,e))) = [e]
76 vbNames :: [Vbind] -> [Var]
79 -- assumes v is not bound in e
80 substIn :: Data a => Var -> Var -> a -> a
81 substIn v newV = everywhereExcept (mkT frob)
82 where frob (Var (Nothing,v1)) | v == v1 = Var (Nothing,newV)
85 substVars :: Data a => [Var] -> [Var] -> a -> a
86 substVars oldVars newVars e = foldl' (\ e1 (old,new) -> substIn old new e1)
87 e (zip oldVars newVars)
90 tdefNames :: [Tdef] -> [Qual Var]
91 tdefNames = concatMap doOne
92 where doOne (Data qtc _ cds) = qtc:(concatMap doCdef cds)
93 doOne (Newtype qtc qtc1 _ _) = [qtc, qtc1]
94 doCdef (Constr qdc _ _) = [qdc]
96 tdefDcons :: [Tdef] -> [Qual Var]
97 tdefDcons = concatMap doOne
98 where doOne (Data _ _ cds) = concatMap doCdef cds
100 doCdef (Constr qdc _ _) = [qdc]
102 tdefTcons :: [Tdef] -> [Qual Var]
103 tdefTcons = concatMap doOne
104 where doOne (Data qtc _ _) = [qtc]
105 doOne (Newtype qtc qtc1 _ _) = [qtc, qtc1]
107 filterVdefgs :: (Vdef -> Bool) -> [Vdefg] -> [Vdefg]
108 filterVdefgs ok = catMaybes . (map dropNames)
109 where dropNames (Nonrec v) | not (ok v) = Nothing
110 dropNames v@(Nonrec _) = Just v
111 dropNames (Rec bs) = case filter ok bs of
113 newBs -> Just (Rec newBs)
115 applyNewtype :: CoercionKind -> [Ty] -> (Ty,Ty)
116 applyNewtype _d@(DefinedCoercion tbs (from,to)) tys =
117 let (tvs,_) = unzip tbs in
118 let res = (substl tvs tys from,substl tvs tys to) in
119 -- trace ("co = " ++ show d ++ " args = " ++ show tys ++ " res = " ++ show res) $
122 {- Simultaneous substitution on types for type variables,
123 renaming as neceessary to avoid capture.
124 No checks for correct kindedness. -}
125 substl :: [Tvar] -> [Ty] -> Ty -> Ty
126 substl tvs ts t = f (zip tvs ts) t
131 Tvar v -> case lookup v env of
134 Tapp t1 t2 -> Tapp (f env t1) (f env t2)
136 if tv `elem` free then
137 Tforall (t',k) (f ((tv,Tvar t'):env) t1)
139 Tforall (tv,k) (f (filter ((/=tv).fst) env) t1)
140 TransCoercion t1 t2 -> TransCoercion (f env t1) (f env t2)
141 SymCoercion t1 -> SymCoercion (f env t1)
142 UnsafeCoercion t1 t2 -> UnsafeCoercion (f env t1) (f env t2)
143 LeftCoercion t1 -> LeftCoercion (f env t1)
144 RightCoercion t1 -> RightCoercion (f env t1)
145 InstCoercion t1 t2 -> InstCoercion (f env t1) (f env t2)
146 where free = foldr union [] (map (freeTvars.snd) env)
150 {- Return free tvars in a type -}
151 freeTvars :: Ty -> [Tvar]
152 freeTvars (Tcon _) = []
153 freeTvars (Tvar v) = [v]
154 freeTvars (Tapp t1 t2) = freeTvars t1 `union` freeTvars t2
155 freeTvars (Tforall (t,_) t1) = delete t (freeTvars t1)
156 freeTvars (TransCoercion t1 t2) = freeTvars t1 `union` freeTvars t2
157 freeTvars (SymCoercion t) = freeTvars t
158 freeTvars (UnsafeCoercion t1 t2) = freeTvars t1 `union` freeTvars t2
159 freeTvars (LeftCoercion t) = freeTvars t
160 freeTvars (RightCoercion t) = freeTvars t
161 freeTvars (InstCoercion t1 t2) = freeTvars t1 `union` freeTvars t2
163 {- Return any tvar *not* in the argument list. -}
164 freshTvar :: [Tvar] -> Tvar
165 freshTvar tvs = maximum ("":tvs) ++ "x" -- one simple way!
167 splitLambda :: Exp -> ([Bind],Exp)
168 splitLambda (Lam vb e) = case splitLambda e of
169 (vbs,rhs) -> (vb:vbs,rhs)
170 splitLambda (Note _ e) = splitLambda e
171 splitLambda e = ([],e)
173 vbinds :: [Bind] -> [(Var,Ty)]
174 vbinds = foldl' stuff []
175 where stuff :: [(Var,Ty)] -> Bind -> [(Var,Ty)]
176 stuff rest (Tb _) = rest
177 stuff rest (Vb p) = p:rest
179 splitBinds :: [Bind] -> ([(Tvar,Kind)],[(Var,Ty)])
180 splitBinds = foldr stuff ([],[])
181 where stuff (Tb t) (tbs,vbs) = (t:tbs,vbs)
182 stuff (Vb v) (tbs,vbs) = (tbs,v:vbs)
184 freeVars :: Exp -> [Qual Var]
185 freeVars (Var v) = [v]
186 freeVars (Dcon _) = []
187 freeVars (Lit _) = []
188 freeVars (App f g) = freeVars f `union` freeVars g
189 freeVars (Appt e _) = freeVars e
190 freeVars (Lam (Tb _) e) = freeVars e
191 freeVars (Lam (Vb (v,_)) e) = delete (unqual v) (freeVars e)
192 freeVars (Let (Nonrec (Vdef (v,_,rhs))) e) = freeVars rhs `union` (delete v (freeVars e))
193 freeVars (Let r@(Rec _) e) = (freeVars e \\ boundVars) `union` (freeVarss rhss \\ boundVars)
194 where boundVars = map unqual $ vdefgNames r
196 freeVars (Case e (v,_) _ alts) = freeVars e `union` (delete v1 (boundVarsAlts alts))
198 boundVarsAlts as = freeVarss rhss \\ (v1:caseVars)
199 where rhss = map (\ a -> case a of
203 caseVars = foldl' union [] (map (\ a -> case a of
205 (map unqual (fst (unzip vbs)))
207 freeVars (Cast e _) = freeVars e
208 freeVars (Note _ e) = freeVars e
209 freeVars (External {}) = []
211 freeVarss :: [Exp] -> [Qual Var]
212 freeVarss = foldl' union [] . map freeVars