2 % (c) The GRASP/AQUA Project, Glasgow University, 1992-1998
4 \section{@VarEnvs@: Variable environments}
8 VarEnv, IdEnv, TyVarEnv,
9 emptyVarEnv, unitVarEnv, mkVarEnv,
10 elemVarEnv, rngVarEnv,
11 extendVarEnv, extendVarEnv_C, extendVarEnvList,
12 plusVarEnv, plusVarEnv_C,
13 delVarEnvList, delVarEnv,
14 lookupVarEnv, lookupVarEnv_NF, lookupWithDefaultVarEnv,
16 modifyVarEnv, modifyVarEnv_Directly,
17 isEmptyVarEnv, foldVarEnv,
20 TidyEnv, emptyTidyEnv,
23 SubstEnv, TyVarSubstEnv, SubstResult(..),
24 emptySubstEnv, substEnvEnv,
25 mkSubstEnv, lookupSubstEnv, extendSubstEnv, extendSubstEnvList,
26 delSubstEnv, delSubstEnvList, noTypeSubst, isEmptySubstEnv
29 #include "HsVersions.h"
31 import {-# SOURCE #-} CoreSyn( CoreExpr )
32 import {-# SOURCE #-} TypeRep( Type )
34 import BasicTypes ( OccInfo )
35 import OccName ( TidyOccEnv, emptyTidyOccEnv )
36 import Var ( Var, Id )
38 import Util ( zipEqual )
42 %************************************************************************
46 %************************************************************************
48 When tidying up print names, we keep a mapping of in-scope occ-names
49 (the TidyOccEnv) and a Var-to-Var of the current renamings.
52 type TidyEnv = (TidyOccEnv, VarEnv Var)
53 emptyTidyEnv = (emptyTidyOccEnv, emptyVarEnv)
57 %************************************************************************
59 \subsection{Substitution environments}
61 %************************************************************************
65 noTys :: SubstResult -> Bool -> Bool
66 noTys (DoneTy ty) no_tys = False
67 noTys other no_tys = no_tys
69 data SubstEnv = SE (VarEnv SubstResult)
70 Bool -- True => definitely no type substitutions in the env
72 noTypeSubst :: SubstEnv -> Bool
73 noTypeSubst (SE _ nt) = nt
75 substEnvEnv :: SubstEnv -> VarEnv SubstResult
76 substEnvEnv (SE env _) = env
78 type TyVarSubstEnv = SubstEnv -- of the form (DoneTy ty) *only*
81 = DoneEx CoreExpr -- Completed term
82 | DoneId Id OccInfo -- Completed term variable, with occurrence info; only
83 -- used by the simplifier
84 | DoneTy Type -- Completed type
85 | ContEx SubstEnv CoreExpr -- A suspended substitution
87 emptySubstEnv :: SubstEnv
88 emptySubstEnv = SE emptyVarEnv True
90 isEmptySubstEnv :: SubstEnv -> Bool
91 isEmptySubstEnv (SE s _) = isEmptyVarEnv s
93 lookupSubstEnv :: SubstEnv -> Var -> Maybe SubstResult
94 lookupSubstEnv (SE s _) v = lookupVarEnv s v
96 extendSubstEnv :: SubstEnv -> Var -> SubstResult -> SubstEnv
97 extendSubstEnv (SE s nt) v r = SE (extendVarEnv s v r) (noTys r nt)
99 mkSubstEnv :: [Var] -> [SubstResult] -> SubstEnv
100 mkSubstEnv bs vs = extendSubstEnvList emptySubstEnv bs vs
102 extendSubstEnvList :: SubstEnv -> [Var] -> [SubstResult] -> SubstEnv
103 extendSubstEnvList env [] [] = env
104 extendSubstEnvList (SE env nt) (b:bs) (r:rs) = extendSubstEnvList (SE (extendVarEnv env b r) (noTys r nt)) bs rs
106 delSubstEnv :: SubstEnv -> Var -> SubstEnv
107 delSubstEnv (SE s nt) v = SE (delVarEnv s v) nt
109 delSubstEnvList :: SubstEnv -> [Var] -> SubstEnv
110 delSubstEnvList (SE s nt) vs = SE (delVarEnvList s vs) nt
114 %************************************************************************
116 \subsection{@VarEnv@s}
118 %************************************************************************
121 type VarEnv elt = UniqFM elt
122 type IdEnv elt = VarEnv elt
123 type TyVarEnv elt = VarEnv elt
125 emptyVarEnv :: VarEnv a
126 mkVarEnv :: [(Var, a)] -> VarEnv a
127 zipVarEnv :: [Var] -> [a] -> VarEnv a
128 unitVarEnv :: Var -> a -> VarEnv a
129 extendVarEnv :: VarEnv a -> Var -> a -> VarEnv a
130 extendVarEnv_C :: (a->a->a) -> VarEnv a -> Var -> a -> VarEnv a
131 plusVarEnv :: VarEnv a -> VarEnv a -> VarEnv a
132 extendVarEnvList :: VarEnv a -> [(Var, a)] -> VarEnv a
134 delVarEnvList :: VarEnv a -> [Var] -> VarEnv a
135 delVarEnv :: VarEnv a -> Var -> VarEnv a
136 plusVarEnv_C :: (a -> a -> a) -> VarEnv a -> VarEnv a -> VarEnv a
137 mapVarEnv :: (a -> b) -> VarEnv a -> VarEnv b
138 modifyVarEnv :: (a -> a) -> VarEnv a -> Var -> VarEnv a
139 rngVarEnv :: VarEnv a -> [a]
141 isEmptyVarEnv :: VarEnv a -> Bool
142 lookupVarEnv :: VarEnv a -> Var -> Maybe a
143 lookupVarEnv_NF :: VarEnv a -> Var -> a
144 lookupWithDefaultVarEnv :: VarEnv a -> a -> Var -> a
145 elemVarEnv :: Var -> VarEnv a -> Bool
146 foldVarEnv :: (a -> b -> b) -> b -> VarEnv a -> b
151 extendVarEnv = addToUFM
152 extendVarEnv_C = addToUFM_C
153 extendVarEnvList = addListToUFM
154 plusVarEnv_C = plusUFM_C
155 delVarEnvList = delListFromUFM
156 delVarEnv = delFromUFM
158 lookupVarEnv = lookupUFM
159 lookupWithDefaultVarEnv = lookupWithDefaultUFM
162 emptyVarEnv = emptyUFM
165 isEmptyVarEnv = isNullUFM
168 zipVarEnv tyvars tys = mkVarEnv (zipEqual "zipVarEnv" tyvars tys)
169 lookupVarEnv_NF env id = case (lookupVarEnv env id) of { Just xx -> xx }
172 @modifyVarEnv@: Look up a thing in the VarEnv,
173 then mash it with the modify function, and put it back.
176 modifyVarEnv mangle_fn env key
177 = case (lookupVarEnv env key) of
179 Just xx -> extendVarEnv env key (mangle_fn xx)
181 modifyVarEnv_Directly mangle_fn env key
182 = case (lookupUFM_Directly env key) of
184 Just xx -> addToUFM_Directly env key (mangle_fn xx)